B. Siva Bhargava Reddy
bhargavbsr@hotmail.com
K.V.R Sir 9am JEE
8099498819
JDBC (Java Database Connectivity):
DEF: JDBC is one of the generic API developed by SUN Micro System and supplied as a part of
a java software to deal with any type of database product to perform various database operations.
Java
Programmer
JDBC API
MS Access
Oracle
SQL
My SQL
SQL Server
DB2
|
|
e.t.c.,
1. Database Programming with java is known as JDBC similarly database programming in
.NET is called DTO (Data Transfer Object) or DAO. The basic aim of JDBC is to
achieve data persistency.
2. The process of storing the data permanently in the form of either in files or in database is
known as data persistency.
3. In earlier software development, if any language programmer wants to achieve the data
persistency then the language programmer must know the Vendor Specific API. For
example if a C programmer want to store the data in Oracle database then C programmer
must know the vendor specific library of Oracle database.
4. If the client organization decide to migrate one database to another database then the C
programmer has completely rewrite the code by learning vendor specific library.
5. It is very difficult process to eliminate this limitation SUN Micros system has developed
a generic API is called JDBC for the java programmers to deal with any number of
databases without learning vendor specific API.
6. In order to deal with JDBC API we must import the packages called java.sql.*,
javax.sql.*. In real world data persistency achieved in two ways they are
1
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7. i) Through the concept of files ii) Through the concept of Database.
8. As a java programmer if we store the data in the form of the files then the data of the file
can be manipulated by any un authorized user so that any files of any programming
language never provides security in terms of username and passwords. Hence industry is
not recommending data storing in files permanently
9. Therefore industry is highly recommended to store the data permanently store in the form
of popular database products they provide enough security to prevent unauthorized
modifications in the form of username and password.
JDBC is a Partial Technology:
1. JDBS is one of the generic API which deals with many number of databases for
performing various operations
2. JDBC is one of the specification/set of rules developed by the SUN Micro system
because of the more famous of java software.
3. The rules of JDBC were implemented by database vendors like Oracle, IBM, Ingress
Corporation e.t.c., in other words programmatically rules of JDBC given by SUN Micro
system in the form of interfaces.
4. We know that interfaces contain Abstract methods. Database vendors have developed
the columns of the classes by implementing the interfaces of JDBC.
5. In later days what classes implemented/developed by database vendors, those classes
becomes product/database dependent classes.
6. Remembering product dependent classes by java programmer is difficult/complex. Here
SUN Micro system has collected all the product dependent classes from database vendors
and prepared common classes and kept in the form of packages.
7. In real world development all packages will be released in the form of jar files (java
archive) along with the interfaces development of JDBC by SUN Micros system.
8. Some of the classes are also developed by Database vendors. Hence JDBC is one of the
Partial Technology but not a language.
9. In pure Technology development interfaces are developed by language vendors
corresponding classes are developed by either server vendors or database vendors
completely.
NOTE: Software is said to be language if and only if rules and their implementations
developed by language vendors only. Languages are installable softwares whereas
technologies are not installable because they are not containing complete implementation by
one vendor.
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Steps for developing a JDBC Application:
1. JDBC Drivers:
Java Program
JDBC Drivers
Database Softwares
1. JDBC Driver is one of the predefined class developed by Database vendors for
establishing the communication between java program and database software or JDBC
Driver is one of middleware layer between java application and database software.
2. Establishing the communication between java program and database software is nothing
but creating an Object of appropriate JDBC Driver for example if we write an Object of
OracleDriver class in our java program then our java program can establish the
communication with oracle database software
3. Similarly when we create an Object of DB2 Driver class then our java program
establishes the communication between DB2 database software.
4. Here Oracle Driver (Oracle Corporation, DB2 Driver(IBM)) are the examples of JDBC
Drivers JDBC drivers are developed by database vendors in the language called java and
they are coming or supplied along with database softwares. A java programmer is not
responsible for development of JDBC drivers but java programmer always use database
Drivers for establishing the communication between java program and database software.
5. SUN Micro system has classified into all available JDBC drivers four categories those
are
i.
Type1 drivers or (JDBC-ODBC bridge drivers)
ii.
Type2 drivers or native drivers
iii.
Type 3 drivers or net protocol drivers
iv.
Type 4 drivers or all java/pure/thin drivers
ODBC Drivers (Open Database Connectivity):
ODBC Drivers:
1. ODBC Drives specifications (rules) developed by Xopen Company. The ODBC
Specification says develop all ODBC Drivers in a language called C. Which is one of the
platform independent language.
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2. All Database vendors come forward and developed drives in a language called C. ODBC
drivers are meant for establishing the communication channel or bridge between non java
applications and database softwares all the database vendors has given the ODBC Drivers
to Xopen Company and Xopen company supplied these ODBC drivers along Microsoft
Operating Systems.
3. The following diagram gives the view about the communication system between java/non
java application and database software.
DSN (Data Source Name):
1. A DSN is a Configured item or variable created in the local machine which always gives
location of the database in simple words DSN is one of the alternative name create by the
programmer for ODBC Drivers.
2. As a java programmer we use DSN in their applications for establishing the
communication between java/non java applications and database software.
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ODBC Driver for
Oracle
Non java – java
application
ODBC Drivers
ODBC Driver
for MySQL
MySQL
databse
ODBC Driver for
Paradax
Database
Paradax
ODBC Driver for
DB2
5
Oracle
database
DB2 database
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ODBC Driver for
MsAccess
Ms Access
Database
Q) What are the differences between JDBC drivers and ODBC drivers?
JDBC Drivers
ODBC Drivers
1. JDBC
Drivers
specification
1. ODBC
Drivers
specification
developed by SUN Micro system and
developed by Xopen and JDBC
JDBC drivers are implemented by
drivers are implemented by Database
Database vendors.
vendors.
2. All database vendors implemented
2. All database vendors implemented
JDBC Drivers in java language.
ODBC Drivers in C language.
3. All the JDBC drivers are Platform
3. All the ODBC drivers are Platform
independent.
dependent.
4. All the JDBC drivers are supplied
4. All the ODBC Drivers are supplied
through database softwares.
for Microsoft Operating Systems.
5. JDBC drivers are purely meant for
5. ODBC Drivers are meant for both
establishing
the
communication
java and non java programmers for
between java applications and
establishing communication between
universal softwares.
database softwares.
6. ODBC drivers are not recommended
6. Industry is highly recommended to
by the industry to communication
use JDBC Drivers to communicate
with the database because they
with the database because they
posses/gives platform dependency.
gives/posses platform independency.
Static Block:
1. In java library we come across various predefined classes which are present in various
predefined packages.
2. While we are executing the java program, the corresponding classes will be loaded in the
main memory and executes static blocks of that class only once first during the loading
time, later executes main() only once.
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3. Each and every time constructors will execute depends on the number of the Objects we
create and execute user defined methods depends on the number of times the programmer
is calling.
4. A class of java may or may not contain static blocks.
EX:
class first
{
first()
{
System.out.println("I am from Constructor");
}
void first()
{
System.out.println("I am from method");
}
static
{
System.out.println("I am from business logic static");
}
}
class stsdemo
{
static
{
System.out.println("I am from execution logic static");
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}
public static void main(String args[])
{
first f=new first();
f.first();
}
}
OUTPUT:
C:\>java stsdemo
I am from execution logic static
I am from business logic static
I am from Constructor
I am from method
Observation point: Here first execution logic static block first execute only once, next business
logic static execute only once, next Constructor will execute each and every time, method also
execute each and every time.
Q) Can we write a java program without main ()?
A) Yes, through static blocks we can execute the java program.
EX:
class first
{
void first()
{
System.out.println("hello");
8
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}
}
class stsdemo
{
static
{
System.out.println("Hello");
}
}
OUTPUT:
C:\>java stsdemo
Hello
Exception in thread "main" java.lang.NoSuchMethodError: main
P) Write a java program which illustrate the concept of static blocks.
//stp.java
package stp;
public class stp
{
static
{
System.out.println("I am from static block");
}
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public stp()
{
System.out.println("stp DC");
}
public void disp()
{
System.out.println("STP-Disp");
}
}
//Stpdemo.java
import stp.*;
class stpdemo
{
public static void main(String args[])
{
try
{
Class c=Class.forName(args[0]);
String cname=c.getName();
System.out.println("Class name="+cname);
}
catch(ClassNotFoundException ce)
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{
System.err.println(args[0]+"class not exists");
}
}
}
OUTPUT:
C:\>java stpdemo stp.stp
I am from static block
Class name=stp.stp
Architecture of Type-1 Driver:
1. Type11 Driver developed by SUN Micro system and it is known as JDBC – ODBC
bridge driver.
2. Type-1 Driver implemented by SUN Micro system in C language. So that Type-1 driver
always posses platform dependent.
3. Type-1 Driver always supplied as a part of Java software
4. Type-1 Driver of SUN Micro system makes use of DSN to communicate with the
database software. As on today real world applications never uses Type-1 Driver but it is
used only for testing purpose.
5. The following Diagram gives architecture of Type-1 Driver.
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The following steps gives to and pro calls between Java program and Database Software.
1. We write java program making use of JDBC API.
2. Java programs makes use of JDBC Driver (Type-1) for establishing the communication
between Java program and Database software.
3. Since Type-1 driver of JDBC is not having the capability to directly communicate with
database software so that Type – 1 Driver makes use of ODBC driver this combination is
known as JDBC-ODBC Bridge. The role of JDBC-ODBC Bridge is to convert java
related calls into Database equivalent calls and Database equivalent calls to java
equivalent calls during its communication.
4. It is not possible to use ODBC Driver in the Java program directly so that we use an alias
name of ODBC driver called DSN which will give collection of Database software where
the programmer is interested in communicating.
5. All Database related calls(queries) are reaching to the Database software through DSN.
6. Database queries are executed by the Database engines in the Database layer
7. 8,9) The result of database software given to the Java application through DSN and
JDBC-ODBC bridge.
10. * JDBC bridge converts Database equivalent calls to Java equivalent calls.
11. The result of the Database reaches to the java program and it will be displayed on the
Console.
In the above steps 1,2,3,4,5 are called “to calls” from Java program and remaining steps
are “pro calls” between Database software and Java application.
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Type-1 Driver allows us to develop only two-tier applications (Java application,
Database Software).
Note:
Type:
JDBC-ODBC bridge
Driver Vendor:
SUN Micro System
Driver name:
sun.jdbc.odbc.JdbcOdbcDriver
Jar file:
rt.jar(jdk 1.5, jdk 1.6/lib)
Software requirement:
jdk1.5/jdk 1.6
Database software:
Oracle 8i/9i/10g/11g.
Implementation language: C
In Type -1 Driver, application development JDBC-ODBC driver name is fixed and DSN
names are verifying from one database software to Database software
Steps for developing JDBC applications: In order to write any JDBC application, SUN Micro
system has prescribed the following guidelines.
1) Load or register the JDBC drivers with the Driver Manager Service.
2) Obtain the communication by making use of Driver Manager Service.
3) Create the statement Object for sending the queries from java program to Database
software.
4) Use statement Object to send the queries from java application to Database software.
5) Java program process the Database result.
6) Close the connection/relinquish (release JDBC Objects).
i)
Load or register the JDBC drivers with the Driver Manager Service: In java
programming we have predefined service called Driver Manager Service and it is
always used for registering or loading the JDBC Drivers. Unless and until loading the
Drivers in the Driver Manager Service, we can’t get any communication with the
Database software registering or loading the Drivers is nothing but creating an Object
of appropriate Driver Class and place that Object in the Driver Manager Service in
Java programming to get the Driver Manager Service we have a predefined class
called Driver Manager which is present in a predefined package called java.sql.*,
java.sql.DriverManager Class contains the following method for loading the Drivers
only once.
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Java.sql.DriverManager
Public static void RegisterDriver
(java.sql.Driver)
Here java.sql.Driver is the super interface(developed by SUN) for all JDBC drivers
(developed by other party Vendor)
class JdbcOdbcDriver implements Driver
{
class OracleDriver implements Driver
{
-------------------}
EX: JdbcOdbceDriver jd=new JdbcOdbcDriver();
DriverManager.registerDriver(jd);
{
System.out.println(“Type-1 Driver loaded”);
}
EX: OracleDriver od=new OracleDriver();
DriverManager.registerDriver(od);
{
System.out.println(“Type-4 Drivers loaded”);
}
The process of registering drivers with Driver Manager Service is known as explicit
drivers registration.
Implicit registration/Loading of the JDBC Drivers in the Driver Manager Service:
Industry is highly recommended to use implicit registration of the drivers with Driver
Manager Service. To perform implicit registration of the drivers we use Class.forName(-)
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EX: Class.forName(sun.jdbc.odbc.JdbcOdbcDriver)
When the above statement is executed the following implicit actions will be performed by
the JVM.
1) JVM loads JdbcOdbc driver class in the main memory of the computer.
2) JVM automatically calls static blocks of JdbcOdbcDriver class only once.
3) As a part of JdbcOdbcDriver class, in the static block SUN Micro System developers has
written the following steps
a) Created an Object of JdbcOdbc Driver class
b) An Object of JdbcOdbcDriver class placed in the Driver Manager Service.
c) In general the above procedure is applicable for all JdbcDrivers.
class JdbcOdbcDriver implements Driver.
{
static
{
----------------JdbcOdbcDriver jd=new JdbcOdbcDriver();
DriverManager.registerDriver(jd);
---------------}
Industry is always recommended to use implicit registration on loading of the drivers
with help of Class.forName(-).
(If we would like to know internal details of class we use Class= beore Class.forname)
ii)
Obtain the connection by making use of DriverManagerService: In order to
obtain a connection from the specified Database the appropriate Jdbc drivers must be
loaded in the DriverManager service first. That is without loading the Drivers
obtaining connection from specific Database is not possible.
In order to get the connection from the Database we must use the following
methods present in DriverManager Service
Java.sql.DriverManager
a) Public static Connection getConnection(String url);
b) Public static Connection getConnection(String url,String uname,String pwd);
c) Public static Connection getConnection(String url,Properties p);
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a) Public static Connection getConnection(String,url): This method is used for obtaining
conncetion from unsecured Database like MS Access, MS Excel e.t.c. because these
database doesn’t contain user name and password.
b) Public static Connection getConnection(String url,String uname,String pwd): This
method is used for obtaining the connection from Secured Database
like
Oracle,DB2,SQL Server e.t.c.,
EX: connection oracon=DriverManager.getConnection(“Jdbc:Odbc:sathya”,”scott”,”tiger”)
connection acon=DriverManager.getConnection(“Jdbc:Odbc:Accdsn)//for Access DB
Here oracon,accon are two indirect Object of java.sql.Connection interfacxe but they are
direct Objects of subclasses of connetion interfaces.
Conncetion interface developed by SUN Micro system and whose sub class developed by
Database vendors.
c) Public static Connection getConnection(String url,Properties p): This method is used
for obtaining both from secured and unsecured Databases. These types of connections are
known as flexible connections.
Syntax for url format of Type-1 Driver:
Main Protocol : subprotocol : DSN
Here in JDBC applications main protocol always represents JDBC and whose role is converts
java related calls into database calls. Sub protocol represents always ODBC and further it will be
changing depends on the Database vendor and the purpose of the protocol is taking the Database
calls and hand over to the Database through DSN. DSN represents an alias name of ODBC
Driver which is configured to the local machine it always locates the connection of the Database
Jdbc:Odbc:Accdsn
Jdbc:Odbc:Oradsn
Jdbc:Odbc:Xldsn
Note:
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1. Jdbc, Odbc are known as proprietary protocols which will establish the communication
between two specific applications.
2. HTTP,FTP,SMTP,POP e.t.c., are known as Application level protocol which will
establish the communication between universal applications.
3. TCP and UDP are known as Network level protocol s and it will establish the
communication between one network and other network.
P) Write a Jdbc application which illustrate the concept of loading the drivers and
obtaining the connection from Oracle database by using Type-1 Driver.
import java.sql.*;
import sun.jdbc.odbc.JdbcOdbcDriver;
class Firstjdbc
{
public static void main(String args[]) throws Exception
{
//step-1
JdbcOdbcDriver jd=new JdbcOdbcDriver();
DriverManager.registerDriver(jd);//explicit driver loading
//Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); //implicit loading
System.out.println("type-1 Driver loading");
//step-2
Connection con=DriverManager.getConnection("jdbc:odbc:siva","scott","tiger");
if(con!=null)
{
System.out.println("connection obtained from oracle");
}
else
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{
System.out.println("connection failed");
}
}
}
/* OUTPUT
C:\>java Firstjdbc
type-1 Driver loading
connection obtained from oracle
*/
iii)
Create the statement Object for sending the queries from java program to
Database software.
In order to send a query to java application database software, we must create an Object od
Statement interface. Statement is one of the predefined interface which is present in
java.sql.* package and whose Object purpose is to carry the query from java application to
Database software.
In order to create an Object of statement interface we use the following method present in
Connection interface java.sql.Connection
public statement CreateStatement()
EX: Statement st=con.CreateStatement();
Here st is an indirect Object of statement interface and it is one of the direct Obejct of sub
class of Statement interface.
Here st is ready to use to take query from java application to the Database software
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4. Use Statement Object to sending the queries to the Database: In order to send queries
from java application to the Database software we use the following methods present in
Statement interface.
Java.sql.Statement
a) public int executeUpdate(String)
b) public ResultSet execute(String)
c) public boolean execute(String)
a) public int executeUpdate(String): Here this method is used for executing non-select
queries(insert,update,delete) the parameter String represents name of the non-selected
query this method returns int values as a return type if intValue is Positive then query is
executed successfully executed. If intValue is zero then query is not executed
successfully.
EX: String qry=”insert into dept values(60,’filename’,’hyd’)
int res =st.executeUpdate(qry);
System.out.println(res+”rows inserted”);
int res1=st.executeUpdate(“delete from emp where deptno=10);
System.out.println(res+”Rows deleted”);
b) public ResultSet execute(String): This method is used for executing select queries the
parameter String represents name of the query the return type of this method is
ResultSet. ResultSet is one of the predefined interface which is used for holding the
number of records after execution of select query in the Database software.
EX: ResultSet rs=st.executeQuery(“select * from dept”);
rs
1
Deptno
10
20
30
2
3
Dname
Finance
HR
Marketing
Loc
Hyderabad
Delhi
Banglore
c) public boolean execute(String): This method is used for executing both select and non
select queries. The return type of this method is boolean if boolean value is true then the
query is executed successfully. If it is false the query is not executed successfully.
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EX: boolean res=st.execute(“select * from dept”);
System.out.println(res) //true.
5. Java program process the Database result: Processing the Database result is nothing
but obtaining the result from Database and use in our java program.
EX: figure 1. In order to retrieve the data from ResultSet interface Object we have two
approaches those are
i)
ii)
Based on Column number or Column name in the form of String type
Based on Column number or Column name in the form of Original type.
In JDBC programming after retrieving the records from the database they are available in the
form of Object of ResultSet interface and whose Database column names with the numbers
1,2,3,------,n. When we create an Object of ResultSet which is by default pointing just
before the first record. To retrieve the further records we need to move ResultSet objects to
further records after checking whether we have next record or not.
Methods in ResultSet:
1.
2.
3.
4.
5.
public boolean next()
public String getString(int Columnno)
public String getString(String Columnname)
public xxx getXxx(int columnno)
public xxx getXxx(String Columnname)
Columnno
Columnname
Columnno
Columnname
String
Original Type
1. public boolean next(): This method returns true provided ResultSet interface Object is
having next record. Once it returns true, the ResultSet interface Object will be point that
particular record. This method returns false provided ResultSet interface Object have
does not have any next record.
2. public String getString(int Columnno)
3. public String getString(String Columnname): These two methods are used to retrieve the
data from the Database in the form of the String based on column number or based on
column name.
EX: ResultSet rs=st.executeQuery(“Select * from dept”);
rs
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Deptno
Dname
Finance
10
20
HR
30
Marketing
Obtaining the records based on column numbers.
Loc
Hyd
Ban
Chn
While(rs.next)
{
String dno=rs.getString(1);
String dname=rs.getString(2);
String loc=rs.getString(3);
System.out.println(dno+” “+dname+” “+loc);
}
Obtain the records based on the column names
While(rs.next)
{
String dno=rs.getString(deptno);
String dname=rs.getString(dname);
String loc=rs.getString(loc);
}
4. public xxx getXxx(int columnno)
5. public xxx getXxx(String Columnname): These methods are used for retrieving the
data of the Database in the original form. Either based on Column number or based on
Column name.
while(rs.next)
{
int deptno=rs.getString(1);
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String dname=rs.getString(2);
String loc=rs.getString(3);
}
Obtaining records based on columns
While(rs.next)
{
Int deptno=rs.getint(deptno);
String dname=rs.getString(dname);
String loc=rs.getString(loc);
}
Note: By default JDBC 2.X features, an Object of ResultSet interface allows us to retrieve
the data only in forward direction. But not in backward direction. This type of ResultSet is
not scrollable “ResultSet”.
P) Write a JDBC program for inserting a record into dept table of Database.
import java.sql.*;
import sun.jdbc.odbc.JdbcOdbcDriver;
class Jdbcnew1
{
public static void main(String args[])throws Exception
{
//step-1
// JdbcOdbcDriver jd=new JdbcOdbcDriver();
//DriverManager.registerDriver(jd); //explicit Registration
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Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
//Step-2
Connection con=DriverManager.getConnection("jdbc:odbc:siva","scott","tiger");
//Step-3
Statement st=con.createStatement();
//Step-4
String qry="insert into dept values(50,'Acc','hyd')";
int res=st.executeUpdate(qry);
//step-5
System.out.println(res+"rows inserted");
//step
st.close();
con.close();
}
}
P) Write a JDBC program to accept empno from cmd prompt and enter values.
import java.sql.*;
import sun.jdbc.odbc.JdbcOdbcDriver;
import java.util.*;
class practicedemo
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{
public static void main(String args[])throws Exception
{
//step-1
// JdbcOdbcDriver jd=new JdbcOdbcDriver();
//DriverManager.registerDriver(jd); //explicit Registration
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
//Step-2
Connection con=DriverManager.getConnection("jdbc:odbc:siva","scott","tiger");
//Step-3
int eno=Integer.parseInt(args[0]);
Scanner s=new Scanner(System.in);
System.out.println("enter emp mumber");
String s1=s.nextLine();
//step-3
Statement st=con.createStatement();
//step-4
ResultSet rs=st.executeQuery("select ename,job,sal from emp where empno="+eno);
//step-5
if(rs.next())
{
24
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String ename=rs.getString(1);
String job=rs.getString(2);
String sal=rs.getString(3);
System.out.println("emp name="+ename);
System.out.println("emp job="+job);
System.out.println("emp sal="+sal);
}
else
{
System.out.println("no record found");
}
rs.close();
st.close();
con.close();
}
}
/* OUTPUT
C:\>java practicedemo 7788
Driver registered
enter emp mumber
7788
emp name=RAJU
25
B. Siva Bhargava Reddy
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K.V.R Sir 9am JEE
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emp job=CLERK
emp sal=5000
*/
Observations:
1. If a JDBC program violates the constraints of a table/Database then we get a predefined
exception called java.sql.Exception.
2. Whatever the Database operations perform on the table(inserting,deleting,modifying)
those operations are auto committed. That is explicitly the JDBC programmer need not
use Committ command.
6. Close Connection/Relinquish(release) JDBC Objects: After completion of Database
operations, it is responsibility of the JDBC programmer to close or release the JDBC
related Objects those are
Close the Objects of ResultSet, Statement and Connection interface.
EX: rs.close();
Con.close();
St.close();
Here close is the method present in ResultSet, Statement and connection interfaces.
P) Write a JDBC program which will remove a record by accepting deptno dynamically.
import java.sql.*;
class prt
{
public static void main(String args[])throws Exception
{
//step-1
Class.forName("oracle.jdbc.driver.OracleDriver");
26
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System.out.println("Driver Loaded");
//Step-2
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection established from Oracle");
//step-3
Statement st=con.createStatement();
int no=Integer.parseInt(args[0]);
int p1=st.executeUpdate("delete from vst where no="+no);
if(p1>0)
System.out.println(p1+"Record deleted");
else
System.out.println("no record found");
st.close();
con.close();
}
}
P) Write a JDBC Program which will select empno, name, salary, designation based on
employee number accept the employee number from command prompt.
import java.sql.*;
import sun.jdbc.odbc.JdbcOdbcDriver;
class Jdbcnew1
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{
public static void main(String args[])throws Exception
{
//step-1
// JdbcOdbcDriver jd=new JdbcOdbcDriver();
//DriverManager.registerDriver(jd); //explicit Registration
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
//Step-2
Connection con=DriverManager.getConnection("jdbc:odbc:siva","scott","tiger");
//Step-3
Statement st=con.createStatement();
//Step-4
int no=Integer.parseInt(args[0]);
ResultSet res=st.executeQuery( "Select * from emp where empno="+no);
//step-5
if(res.next())
{
System.out.println("Employee name"+res.getString(2));
System.out.println("Employee name"+res.getString(4));
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System.out.println("Employee name"+res.getString(6));
}
//Step-6
st.close();
con.close();
}
}
Type -1 Driver Advantages:
1. By using Type-1 Driver one can communicate with any number of Databases.
2. Type-1 Driver is easy to implement and easy to remember for establishing the
communication between java application and Database software.
Disadvantages:
1. Type-1 Driver implemented by SUN Micro System in C language so that Type-1 Driver
possesses platform dependency. This is not recommended.
2. In order to use Type-1 Driver, it is mandatory to JDBC programmer to create DSN in the
local machine. So that local settings of the PC are not recommended because when the
JDBC application us changing from one PC to another local PC programmer need to
perform required local settings.
3. Type-1 Driver gives more number of to and pro calls in other words there exists more
number of round trips between java application and Database software which makes the
JDBC application to get less performance.
4. Type-1 Driver is used only for testing purpose but not for real implementation purpose
for application development.
5. Type-1 Driver allows us to develop two tier applications only but not three tier
applications.
Type-4 Deriver (All Java, pure Java, Thin):
1. Type-4 Drivers developed by Database vendors.
2. Type-4 Drivers are supplied along with Database software for example Oracle
corporation developed Type-4 Driver on the name of predefined class called
OracleDriver and it is present in a predefined package called oracle.jdbc.driver.*;
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3. IBM has developed Type-4 Driver name DB2 Driver and it is present in predefined
package called ibm.jdbc.Driver.*. All the Database vendors has developed Type-4 driver
in Java language so that all Type-4 drivers possesses platform independency. While we
are using Type-4 Driver as a part of our JDBC application we doesn’t require any DSN.
Architecture:
Application Layer
Database Layer
Java Application
Database Software
1
JDBC API
4
7
6
2
J
D
B
C
5 5
5
3
In the above architecture the Type-4 Driver converts java calls to Database equivalent calls
and Database equivalent calls to java related calls. Oracle Corporation has supplied OracleDriver
class in the following jar files. Classes12.jar or jdbc14.jar.
As a java Developer when we use OracleDriver, it is mandatory for the JDBC programmer to
set classpath. All the above jar files are present in Oracle software in the following location.
C:\oracle\product\10.2.0\db_1\jdbc\lib\classes12.jar;.;
Note to show classpath after setting it just type echo %classpath%
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Set classpath= C:\oracle\product\10.2.0\db_1\jdbc\lib\classes12.jar;.;
Before compiling the JDBC program we need to set the above class path.
Loading or Registering Type-4 Driver(OracleDriver):
1. Loading implicitly Class.forName( “oracle.jdbc.driver.OracleDriver”)
2. Loading explicitly
OracleDriver od=new oracle.jdbc.driver.OracleDriver;
(or)
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver);
Obtaining the connection from the Database software by using Type-4 Driver:
Syn: Main protocol: sub protocol: Logical name of Type-4: @ DNS or IP address: port number:
Serive id
a) Here Main Protocol is always JDBC
b) Sub protocol is always represents Database vendor name (for example Oracle Database
vendor the sub protocol is Oracle).
c) Logical name of Type-4 of OracleDriver is always thin
d) DNS(Domain Name Service): Represents physical name of the machine where the
Database software resides the default DNS of every computer is localhost ( we can write
out IP address). IP address means internet protocol address of physical machine where
Database software resides. By default IP address of every machine is 127.0.0.1.
e) Port Number: It is one of the Logical numerical ID” where the Database software is
running. The default protnumber of Oracle 1521(fixed) can’t be change.
f) Service ID: It is one of the alternative name or alias name for universal software called
Oracle, when it is installed in our pc. To find the Service ID of Oracle Database use the
following
SQL> select * from globalname
 Alternatively we can find the service id and port number from one of the file called
tnsnames.ora which is found in D:/oracle/ora92/network/admin folder
 Another alternative way is go to search and type tnsname.ora
EX: jdbc:oracle:thin:@localhost:1521:sathya
Q) What will you give in the place of localhost in Type-4 driver?
A) The destination machine host name. For example it is web application then remove host name
and port number and give proper url.
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Note: Summary of OracleDriver(Type-4)
Driver Name
: OracleDriver
Fully Qualified Name: oracle.jdbc.driver.OracleDriver
Jar files
: Class111.jar, Classes12.jar
Vendor Name
: Oracle Corporation
Implementation
Language
: Java
Logical Name
: thin
P) Write a java program which will load Type-4 Drivers and Obtain Type-4 Driver by
using OracleDriver and obtain the connection from Oracle.
import java.sql.*;
import oracle.jdbc.driver.OracleDriver;
class practicedemo
{
public static void main(String args[])throws Exception
{
//OracleDriver od=new OracleDriver();
// DriverManager.registerDriver(od);
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("drivers loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
32
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System.out.println("Connection Obtained from oracle");
}
}
Note: We can insert like this but it is not recommended approach
P) Write a JDBC program to insert a record into Database table.
import java.sql.*;
class jdbcprog2
{
public static void main(String args[]) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Drivers loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection Obtained");
Statement st=con.createStatement();
String qry="insert into sps values(50,'Acc',5000)";
int res= st.executeUpdate(qry);
st.close();
con.close();
if(res>0)
{
System.out.println(res+"one row inserted");
}
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else
{
System.out.println(res+"not inserted");
}
}
}
P) Write a JDBC Program to give input from keyboard and get result.
import java.sql.*;
import java.util.*;
//import oracle.jdbc.driver.OracleDriver;
class prt
{
public static void main(String args[])throws Exception
{
// OracleDriver od=new OracleDriver();
//DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("drivers loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection Obtained from oracle");
int eno=Integer.parseInt(args[0]);
Scanner s=new Scanner(System.in);
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System.out.println("enter emp mumber");
String s1=s.nextLine();
//step-3
Statement st=con.createStatement();
//step-4
ResultSet rs=st.executeQuery("select ename,job,sal from emp where empno="+eno);
//step-5
if(rs.next())
{
String ename=rs.getString(1);
String job=rs.getString(2);
String sal=rs.getString(3);
System.out.println("emp name="+ename);
System.out.println("emp job="+job);
System.out.println("emp sal="+sal);
}
else
{
System.out.println("no record found");
}
rs.close();
st.close();
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con.close();
}
}
To perform Delete operation
import java.sql.*;
import java.util.*;
class practicedemo
{
public static void main(String args[])throws Exception
{
//step-1
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Driver Loaded");
//Step-2
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection established from Oracle");
//step-3
Statement st=con.createStatement();
int no=Integer.parseInt(args[0]);
Scanner s=new Scanner(System.in);
String s1=s.nextLine();
int p1=st.executeUpdate("delete from vst where no="+no);
System.out.println("enter a number to delete record");
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System.out.println("One record deleted sucessfully");
st.close();
con.close();
}
}
Q) What are
Class.forName(-)
the
differences
betweenDriverManager.registrationDriver
DriverManager.registerDriver
1. This statement is used for registering or
loading the Drivers explicitly.
2. This Statement verifies the JdbcDriver
availability at compile time and
registered at runtime time.
3. This approach is not recommended by
industry because explicit driver
registration done by Java programmer.
and
Class.forName(-)
1. This statement is used for registering or
loading the Drivers implicitly with the
help of inbuilt static blocks.
2. This Statement verifies the JdbcDriver
availability and registration at runtime.
3. This approach is recommended by
industry because implicit driver
registration
done
by
Drivers
Developers(Database developers)
Dealing with MS Access: we know that MS Access is one of the partial RDBMS product
because all the rules of RDBMS (Codd Rules) are not completely satisfy. Microsoft has not
develop any Type-4 Driver to dealing with MS Access Database. MS Access doesnot contain
user name and passwords. In general any universal Database is containing user names and
passwords such Database vendors develops Type-4 driver for directly interacting such Database.
EX: Oracle, DB2, Sybase e.t.c.,
In general if any Database product does not contain any user name and password, there is no
Type-4 Driver developed by Database vendors. As a Java programmer to retrieve the data or to
perform various Database operations we use Type-1 Driver with the help of DSN Creation.
EX: MS Access, MS Excel e.t.c.,
Steps for dealing with MS Access:
1. Create a Database in MS Access.
2. Create DSN.
37
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3. Write a JDBC code to communicate with MS Access.
P) Write a JDBC program to retrieve the data from MS Access.
import java.sql.*;
import sun.jdbc.odbc.JdbcOdbcDriver;
import java.util.*;
class practicedemo1
{
public static void main(String args[])throws Exception
{
//step-1
// JdbcOdbcDriver jd=new JdbcOdbcDriver();
//DriverManager.registerDriver(jd); //explicit Registration
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
//Step-2
Connection con=DriverManager.getConnection("jdbc:odbc:asps");
//Step-3
int eno=Integer.parseInt(args[0]);
Scanner s=new Scanner(System.in);
System.out.println("enter emp mumber");
String s1=s.nextLine();
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//step-3
Statement st=con.createStatement();
//step-4
ResultSet rs=st.executeQuery("select ename,job,sal from emp where empno="+eno);
//step-5
if(rs.next())
{
String ename=rs.getString(1);
String job=rs.getString(2);
String sal=rs.getString(3);
System.out.println("emp name="+ename);
System.out.println("emp job="+job);
System.out.println("emp sal="+sal);
}
else
{
System.out.println("no record found");
}
rs.close();
st.close();
con.close();
}
}
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/* OUTPUT
C:\>java practicedemo 7788
Driver registered
enter emp mumber
7788
emp name=RAJU
emp job=CLERK
emp sal=5000
*/
Dealing with MS Excel: we know that MS Excel is meant for financial calculations in the areas
like banking, insurance, audit e.t.c. In the most of the real world applications development MS
Excel will be used a minor Database and Oracle as a major Database Like MS Access, MS Excel
also does not have user name and password. So that vendor Microsoft has not developed any
Type-4 Driver. As a Java programmer to interact with the MS Excel we need to use Type-1
Driver by creating a DSN for MS Excel.
P) Write a JDBC Code for which makes use of DSN of Excel sheet and select the data.
import java.sql.*;
//import sun.jdbc.odbc.JdbcOdbcDriver;
import java.util.*;
class prt
{
public static void main(String args[])throws Exception
{
//step-1
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// JdbcOdbcDriver jd=new JdbcOdbcDriver();
//DriverManager.registerDriver(jd); //explicit Registration
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
//Step-2
Connection con=DriverManager.getConnection("jdbc:odbc:xldsn");
//Step-3
int eno=Integer.parseInt(args[0]);
Scanner s=new Scanner(System.in);
System.out.println("enter emp mumber");
String s1=s.nextLine();
//step-3
Statement st=con.createStatement();
//step-4
ResultSet rs=st.executeQuery("select * from [emp$] where empno="+eno);
//step-5
if(rs.next())
{
String empno=rs.getString(1);
String ename=rs.getString(2);
String sal=rs.getString(3);
System.out.println("emp name="+empno);
System.out.println("emp job="+ename);
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System.out.println("emp sal="+sal);
}
else
{
System.out.println("no record found");
}
rs.close();
st.close();
con.close();
}
}
Note: We can’t perform update, insert, delete in MS Excel.
Dealing with CSV file:
CSV file: CSV file stands for comma separated value.
Sathya.csv(Sathya.txt)
Stno,sname,marks
10 , Siva,
99
20 , Bhargav 100
30, Reddy
98
CSV file is one of the text file to be created in text editors(note pad, notepad ++) e.t.c., and it
must be saved on some file name with an extension eiter .csv or .txt
CSV file contains multiple rows treated as records and those record values must be separated by
coma (,). Since we are creating the file either in notepad or notepad ++ e.t.c. there is no specific
driver so that we need to use Type-1 driver to retrieve the data from CSV file by creating DSN
(Choose Microsoft Text Driver (*.txt, *.csv).
P) Write a Program for Data retrieval for CSV file.
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import java.sql.*;
import java.util.*;
class sturec
{
public static void main(String args[])throws Exception
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
Connection con=DriverManager.getConnection("jdbc:odbc:csv");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from sturec.csv");
while(rs.next())
{
System.out.println(rs.getString(1)+" "+rs.getString(2));
}
rs.close();
st.close();
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con.close();
}
}
Note: We can’t perform insert, delete, update operations on CSV file.
Pre Compiled or Dynamic Queries: In our earlier applications what are all queries we have
submitted through the Statement interface Object to the Database software are known as Static
queries. While the static queries are executing in the Database software they participated in three
phases they are
1. Parsing Phase
2. Compilation Phase
3. Execution Phase
Parsing Phase:
1.
2.
3.
4.
5.
In Parsing Phase the Token of the query (Token means separating the query that means
insert, into e.t.c.,) is known as splitting or parsing phase.
In compilation Phase syntactical errors of will be checked by the Database engines.
Executing the query phase is nothing but obtaining the result from the Database software.
Whenever we submit same query multiple times through the Statement interface Object
then the same query participates in parsing phase and compilation phase which is not a
recommended process.
Because it takes more amount of time for parsing and compilation phases and leads Lack
of Performance.
To avoid these problems it is highly recommended to use the concept of Dynamic/ Pre
compiled queries.
Static Query def: A static query is one which always participates in repeatedly in parsing,
compilation and execution phase (OR)
If any query executed through Statement interface Object then such type of queries we knew as
static queries.
Definition of Dynamic queries: A dynamic query is one which always participates in only once
in parsing and compilation phase and repeatedly in execution phase. (OR)
If any query is submitted to the Database by using PreparedStatement interface then those
queries are known as Dynamic/precompiled queries.
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Hence industry is not recommended to execute the same type of query with Statement interface
and it is highly recommended to execute the same type of the query multiple times with help of
PreparedStatement interface.
Steps and guidelines to executing Precompiled/Dynamic queries:
1. Prepare a dynamic query
EX: String qry1=”insert into emp values(?,?,?)
String qry2=”Select * from emp”;
2. Here ? (question marks) are known as place holders/indexed/positional parameters and
whose numbers start from 1,2,----,n from left to right Associativity.
3. Create an Object of PreparedStatement interface for executing dynamic queries to create
Object of PreparedStatement. We use the following method which is present in
Connection interface.
Public PrepatedStatement PreparedStatement(String)
Here the parameter String represents name of the Dynamic query in Step-1.
EX: PrepatedStatement ps = con.preparedStatement(qry1).
Here PrepatedStatement is the sub interface of Statement interface. So that all the methods of
Statement interface are inherited into PreparedStatement. Here ps is the indirect Object of
Prepared interface and it is one of the direct Object of sub class of PreparedStatement interface.
4. Set values for positional parameters. Set the values for the positional parameters we use
the following generalized method present in PreparedStatement.
java.sql.PreparedStatement
public void setXxx(int position number, xxx value);
Here xxx represents Fundametal and String datatype.
EX: ps.SetInt(60)
Ps.SetString(2,’Sathya’)
Execute select and non select dynamic queries. To execute these queries we use following
methods.
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java.sql.PreparedStatement
a)
b)
c)
5.
Public int executeUpdate()
Public ResultSet executeQuery()
Public boolean execute()
int res=ps.executeUpdate();
if(res>0)
{
System.out.println(res+”row inserted”);
}
else
{
System.out.println(“record not inserted”);
}
6. Close or terminate all the JDBC stream Objects associated with dynamic queries.
EX: rs.close();
ps.close();
con.clsoe();
EX:
import java.sql.*;
import java.util.*;
class jdbc90
{
public static void main(String args[]) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
//Prepare the dynamic query
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String qry="select * from emp where empno=?";
PreparedStatement ps=con.prepareStatement(qry);
//set the values for the positional paramerters
ps.setInt(1,9999);
//Create dynamic select query
ResultSet rs=ps.executeQuery();
if(rs.next())
{
String empno1=rs.getString(1);
String ename1=rs.getString(2);
System.out.println(empno1+" "+ename1);
while(rs.next())
{
String empno=rs.getString(1);
String ename=rs.getString(2);
System.out.println(empno+" "+ename);
}
}
else
{
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System.out.println("No Record found");
}
rs.close();
ps.close();
con.close();
}
}
//Write same program with String Positional Parameter
import java.sql.*;
import java.util.*;
class jdbc90
{
public static void main(String args[]) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
//Prepare the dynamic query
String qry="select * from emp where ename like ?";
PreparedStatement ps=con.prepareStatement(qry);
//set the values for the positional paramerters
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ps.setString(1,"S%");
//Create dynamic select query
ResultSet rs=ps.executeQuery();
if(rs.next())
{
String empno1=rs.getString(1);
String ename1=rs.getString(2);
System.out.println(empno1+" "+ename1);
while(rs.next())
{
String empno=rs.getString(1);
String ename=rs.getString(2);
System.out.println(empno+" "+ename);
}
}
else
{
System.out.println("No Record found");
}
rs.close();
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ps.close();
con.close();
}
}
/*Observations: Here we have to observe the positional parameters. In this program no need to
keep postional
String parameters in single quotes*/
P) Write a JDBC Program which will insert number of records in the dept Database by
accepting dept number, dname and location from the keyboard by using
PreparedStatement.
import java.sql.*;
import java.util.*;
class practicedemo
{
public static void main(String args[]) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
String qry="insert into dept values(?,?,?)";
PreparedStatement ps=con.prepareStatement(qry);
Scanner s=new Scanner(System.in);
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System.out.println("enter dept number");
int DEPTNO=Integer.parseInt(s.nextLine());
System.out.println("Enter dept name");
String DNAME=s.nextLine();
System.out.println("Enter location");
String LOC=s.nextLine();
//set the values for positional parameters
ps.setInt(1,DEPTNO);
ps.setString(2,DNAME);
ps.setString(3,LOC);
//executing Dynamic query insertion
int res=ps.executeUpdate();
if(res>0)
{
System.out.println(res+"row inserted");
}
else
{
System.out.println("Record not inserted");
}
//close all Objects
ps.close();
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con.close();
}
}
P) Write a JDBC Program which will list employee name and employee designation and
their numbers and whose salary list between 1000 and 3000.
import java.sql.*;
import java.util.*;
class jdbc90
{
public static void main(String args[]) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
//Prepare the dynamic query
String qry="select empno,ename,job,sal from emp where sal between ? and ?";
PreparedStatement ps=con.prepareStatement(qry);
//set the values for the positional paramerters
ps.setFloat(1,1000.0f);
ps.setFloat(2,2000.0f);
//Create dynamic select query
ResultSet rs=ps.executeQuery();
if(rs.next())
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{
String empno1=rs.getString(1);
String ename1=rs.getString(2);
System.out.println(empno1+" "+ename1);
while(rs.next())
{
String empno=rs.getString(1);
String ename=rs.getString(2);
System.out.println(empno+" "+ename);
}
}
else
{
System.out.println("No Record found");
}
rs.close();
ps.close();
con.close();
}
}
P) Write a Java Program which will copy the Excel Sheet Database to the Oracle Database.
import java.sql.*;
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class practicedemo
{
public static void main(String args[])throws Exception
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection xcon=DriverManager.getConnection("jdbc:odbc:xldsn");
System.out.println("connection obtained from Excel");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("connection obtained from Oracle");
Statement st=xcon.createStatement();
PreparedStatement ps=con.prepareStatement("insert into student values(?,?,?)");
//get the data from excel
ResultSet rs=st.executeQuery("select * from [student$]");
//insert the excel record into Oracle
while(rs.next())
{
String sno=rs.getString(1);
String sname=rs.getString(2);
String address=rs.getString(3);
ps.setString(1,sno);
ps.setString(2,sname);
ps.setString(3,address);
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int res=ps.executeUpdate();
System.out.println(res+"row inserted");
}
System.out.println("Data Transfered from excel to Oracle");
rs.close();
ps.close();
st.close();
con.close();
xcon.close();
}
}
Note: To execute the above Java program the Java programmer must follow the following pre
requisites.
1. Create the Worksheet and rename the worksheet as student.
2. Ensure we must create a DSN for Excel worksheet.
3. Ensure the Java programmer must use Type-1 Driver for retrieving the data from Excel
because it is one of the unsecured.
4. As per Oracle Database concerned, the Java programmer must create student table with
the same columns like Excel and use Type-4 driver to interact with Oracle Database.
Differences between Statement and PreparedStatement
Statement
PreparedStatement
1. Statement is one of the super interface
1. PreparedStatement is one of the sub
for the PreparedStatement interface.
interface for the Statement interface.
2. What are all queries submitted through
2. What are all queries submitted through
the Statement interface such queries are
the PreparedStatement interface such
known as static queries.
queries are known as dynamic or
precompiled queries.
3. Queries
of
Statement
interface
3. Queries of PreparedStatement interface
participates repeatedly in parsing and
only once in participating compilation
compilation phase.
phase.
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4. Statement interface object is highly
recommended to execute different types
of queries at different times.
5. The data of static queries of Statement
interface participates in both parsing
and compilation phase.
4. PreparedStatement interface Object is
highly recommended to execute same
type of query multiple times.
5. The data of dynamic queries of
PreparedStatement participating only at
execution phase.
Stored Procedures: In JDBC application development so for we executed all the queries either
by using Statement interface or by using PreparedStatement interface. Each and every JDBC
application belongs to either 2 ties or 3 tier application. A JDBC 2 tier application contains two
categories of programs they are
a) Java program
b) Database Software
a) Java Program: A Java program is always treated as a Client Program. And by default it
contains the following logics.
i.
Presentation Logic
ii.
Persisting Logic.
iii.
Business Logics.
i.
Presentation Logic: Presentation Logic always gives physical visualization of the
application regarding input and output.
EX: The block of Statements which write for accepting stdno, sname and three subjects
marks on the console is comes under presentation logic.
ii.
Persistence Logic: Persistence Logic contains set of queries insert, update, delete,
select on various Database operations.
EX: The block of Statements we write inserting sno, sname and three subject marks into the
Database comes under persisting logic.
iii.
Business Logic: Business logic contains accepting the input and performs some
calculations. In general depends on the input if we are able to give appropriate output
then it is known as business logic.
EX: The block of statements which will accept three subjects marks and calculates the total
and decides the grade is comes under business logic. Hence by default any Java program
contains the above three logics then it is known as Fat client applications.
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Database Software: Database software is not containing any specified logic(in earlier
application development). These type of Database software is known as Thing server. In
other words every JDBC 2 tier architecture application is containing two layers/sub
architectures they are
1. Fat client/ Thin server
2. Thin client/ Fat server.
Limitations of Fat client/ thin server architecture:
1. To and Pro calls are more between Java program and Database software.
2. Network traffic flow is more.
3. Performance of JDBC application is renewed.
To avoid the above limitation we use revised architecture called thin client fat server
application.

What are all queries we executed with Statement interface and PreparedStatement
interface such applications satisfies fat client/thin server architecture. To develop thin
client/fat server architecture related application development we need to use of a
Predefined interface called java.sql.CallableStatement.
 A thin Client always contains presentation logic only. A fat server always contains both
persistency and business logic. In real world application development all the real world
popular Database vendors provides concept called Stored Procedures for implementing
thin client/ fat server architecture for providing significant advantages.
 Stored Procedure: The block of statements which deals with both persistency logic and
business logic resides in the Database software in the form of a program known as a
Stored Procedure. (OR)
 A set of queries which deals with both persistency logic and business logic return in the
form of a PL/SQL program and reside in the Database is known as Stored Procedures.
These are classified into two types those are
1. Function
2. Procedure
1. Function: A Function is sub program of a main program which will return either on
value or one.
Syntax for function:
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Create or replace function <function name> (list of formal parameters if any) return <return
type>
as/is
local variables
begin
block of statement(s);
end;
EX: Create a function in Oracle for computing sum of two numbers.
create or replace function kin(a in number,
b in number)
return number
is
c number;
begin
C:=a+b;
return c;
end;
P) Create a function which will compute sum, subtraction and multiplication of two
numbers.
create or replace function aop(a in number,
b in number, d out number, e out number)
return number
is
c number;
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begin
C:=a+b;
d:=a-b;
e:=a*b;
return c;
end;
import java.sql.*;
import java.util.*;
class Jdbcpro4
{
public static void main(String args[])throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Drivers loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection Obtained");
Scanner s=new Scanner(System.in);
System.out.println("enter first value");
String s1=s.nextLine();
System.out.println("enter second value");
String s2=s.nextLine();
System.out.println("enter Third value");
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String s3=s.nextLine();
System.out.println("enter Fourth value");
String s4=s.nextLine();
int n1=Integer.parseInt(s1);
int n2=Integer.parseInt(s2);
int n3=Integer.parseInt(s3);
int n4=Integer.parseInt(s4);
//step-1
//we must create kin() in Oracle
//step-2
CallableStatement cs=con.prepareCall("{?=call aop(?,?,?,?)}");
//step-3
cs.setInt(2,n1);
cs.setInt(3,n2);
//step-4
cs.registerOutParameter(1,Types.INTEGER);
cs.registerOutParameter(4,Types.INTEGER);
cs.registerOutParameter(5,Types.INTEGER);
//step-5
cs.execute();
//step-6
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int res=cs.getInt(1);
int res1=cs.getInt(4);
int res2=cs.getInt(5);
System.out.println("result="+res);
System.out.println("result="+res1);
System.out.println("result="+res2);
cs.close();
con.close();
}
}
OUTPUT
Drivers loaded
Connection Obtained
enter first value
1
enter second value
2
enter Third value
3
enter Fourth value
4
result=3
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result=-1
result=2
In the above example OUT variables represents output variables which contain the output of the
function implicitly. If we won’t write it takes as IN variable.
As a Java programmer we call name of the funtction( EX: aop) form the JDBC program
Procedure: Procedure always returns either one or more or none.
Syntax: Create or replace procedure<procedure name> list of formal parameters if any as/is
Local variables
Begin
Block of Statements
Guidelines/ steps for executing Stored procedures from JDBC application: SUN Micro
system has prescribed the following guidelines for stored procedures as a part of JDBC
application development.
i)
Prepare a call for invoking a function or procedure which resides in the Database
software.
Syntax: (For function call)
1 2 3, --------4
String sf=”{?=call<fun name>(?,?,?,--------,?)
In the above Syntax1 Question Mark(?) -1 represents output parameter and other question
marks both the syntaxes represents mixture if input and output parameters.
12
EX: String s1=”{?=Call Sum(?,?)}”
ii)
Create an Object of java.sql.CallableStatement for executing Stored Procedure(either
function or procedure) to execute an Object of CallableStatment we use the following
method.
Java.sql.Connection
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Public CallableStatement prepareCall(String)
Here String parameter4 represents name of the Stored Procedure
EX: CallableStatement cs=con.prepareStatement(S1);
Here cs is an indirect Object of CallableStatement indirect Object of CallableStatement
interface but it is one of the directObject of subclass of CallableStatement interface.
iii)
Set the values for positional parameters which are nothing but setting the input values
or input parameters.
EX: cs.setInt(2,10)
cs.setInt(2,20)
iv)
Register which parameter to register the output parameters we use the following
method which is present in java.sql.CallableStatement
Public void registerOutputParameter(int output
int )
Positional
JDBC equivalant
Parameters
datatype
EX: cs.registerOutParameters(1, Types.INTEGER)
Types.INTEGER maps number datatype of Oracle into int datatype of Java. VARCHAR
maps varchar of Oracle into int Datatype of Java. Types.VARCHAR maps varchar of Oracle
String datatype.
v)
Execute the Stored Procedure to execute the Stored Procedure use the following
method present in CallableStatement
public boolean execute()
If the Stored Procedure executes successfully then it returns true otherwise it returns false.
EX: cs.execute()
vi)
Obtain the result of Stored Procedure which is nothing bur retrieving value form OUT
parameter to retrieve the value from OUT parameter we use the following generalized
method which is present in CallableStatement interface.
Public xxx get Xxx(int output positional parameter number )
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Here xxx represents any fundamental datatype String and date
int res=cs.getInt(1);
1 is out parameter position number.
System.out.println(“sum=”+res);
vii)
Close or terminate all the JDBC Objects which are associated with JDBC application.
cs.close()
con.close()
P) Write a JDBC Program which will execute a function of Oracle sum through the
JDBC program.
import java.sql.*;
import java.util.*;
class calls1
{
public static void main(String args[])throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Drivers loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection Obtained");
Scanner s=new Scanner(System.in);
System.out.println("enter first value");
String s1=s.nextLine();
System.out.println("enter second value");
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String s2=s.nextLine();
int n1=Integer.parseInt(s1);
int n2=Integer.parseInt(s2);
//step-1
//we must create kin() in Oracle
//step-2
CallableStatement cs=con.prepareCall("{?=call kin(?,?)}");
//step-3
cs.setInt(2,n1);
cs.setInt(3,n2);
//step-4
cs.registerOutParameter(1,Types.INTEGER);
//step-5
cs.execute();
//step-6
int res=cs.getInt(1);
System.out.println("result="+res);
cs.close();
con.close();
}
}
OUTPUT:
C:\>javac calls1.java
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C:\>java calls1
Drivers loaded
Connection Obtained
enter first value
2
enter second value
3
result=5
NOTE: While we are executing stored procedures it is recommended to use Type-4 drivers
but not Type-1 drivers because Type-4 driver development takes care by Database vendors
and they supports to execute their Stored Procedures.
P) Write a procedure which will accept student number, student name and marks in three
subjects. This procedure calculates Total marks and it will decide result(result=pass
provided student should secure minimum 40 in each subject otherwise result fail) This
procedure must also store student no, student name, thress subjects marks, total marks and
result in a table called student.
create or replace procedure result(sno number, sname varchar,
m1 number,m2 number, m3 number, tot out number, res out varchar) as
begin
tot:=m1+m2+m3;
if((m1<40)or (m2<40) or (m3<40)) then
res:='fail';
else
res:='pass';
end if;
insert into student values(sno ,sname , m1,m2,m3,tot,res);
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end;
/
P) Write a JDBC program which illustrate the concept of executing the procedure or a
JDBC program must accept stdno, sname, marks in three subjects and result obtain
total marks and result.
import java.sql.*;
import java.util.*;
class Jdbcpro
{
public static void main(String[] args)throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Orcle driver loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection obtained form Oracle");
Scanner s=new Scanner(System.in);
System.out.println("Enter student number");
int sno=Integer.parseInt(s.nextLine());
System.out.println("Enter student name");
String sname=s.nextLine();
System.out.println("Enter marks in sub1");
int m1=Integer.parseInt(s.nextLine());
System.out.println("Enter marks in second subject");
int m2=Integer.parseInt(s.nextLine());
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System.out.println("Enter marks in Third subject");
int m3=Integer.parseInt(s.nextLine());
//step-1
// We should create procedure result in Database
//step-2
CallableStatement cs=con.prepareCall("{call result(?,?,?,?,?,?,?)}");
//step-3
cs.setInt(1,sno);
cs.setString(2,sname);
cs.setInt(3,m1);
cs.setInt(4,m2);
cs.setInt(5,m3);
//step-4
cs.registerOutParameter(6,Types.INTEGER);
cs.registerOutParameter(7,Types.VARCHAR);
//step-5
cs.execute();
//step-6
int tot=cs.getInt(6);
String res=cs.getString(7);
System.out.println("total marks="+tot);
System.out.println("result="+res);
//step-7
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cs.close();
con.close();
}
}
OUTPUT:
C:\>java Jdbcpro
Orcle driver loaded
Connection obtained form Oracle
Enter student number
10
Enter student name
99
Enter marks in sub1
98
Enter marks in second subject
99
Enter marks in Third subject
0
total marks=197
result =fail
Create a function which will accept employee number and percentage of salary to be
hike salary to be updated in the Database and it should be returned to the JDBC
application.
create or replace function result1(eno number, hike number)
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return
number
as
sal1 number;
begin
select sal into sal1 from emp where empno=eno;
sal1:=sal1+(sal1*hike);
update emp set sal=sal1;
return sal1;
end;
import java.sql.*;
import java.util.*;
class Jdbcpro
{
public static void main(String[] args)throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Orcle driver loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection obtained form Oracle");
Scanner s=new Scanner(System.in);
System.out.println("Enter employee number");
int eno=Integer.parseInt(s.nextLine());
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System.out.println("Enter hiked sal");
int hike=Integer.parseInt(s.nextLine());
//step-1
// We should create procedure result in Database
//step-2
CallableStatement cs=con.prepareCall("{?=call res1(?,?)}");
//step-3
cs.setInt(2,eno);
cs.setInt(3,hike);
//step-4
cs.registerOutParameter(1,Types.FLOAT);
//step-5
cs.execute();
//step-6
float sal=cs.getFloat(1);
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from emp");
if(rs.next())
{
String empno=rs.getString(1);
String ename=rs.getString(2);
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int sal1=rs.getInt(5);
System.out.println(empno+" "+"employee number");
System.out.println(ename+" "+"employee name");
System.out.println(sal1+" "+"salary");
}
//step-7
rs.close();
st.close();
cs.close();
con.close();
}
}
/*OUTPUT
Orcle driver loaded
Connection obtained form Oracle
Enter employee number
7788
Enter hiked sal
1
7788 employee number
CLERK employee name
11632
salary
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*/
Q) What is the purpose of the Type class?
A) Types class is one of the predefined class present in java.sql.* package. This class contains all
the JDBC equivalent data types in the form of public static final int data members. The purpose
of Types class is mapping the Database datatypes into Java data types and Java data types into
Database data types the following table gives mapping process.
Java Datatype
1. int
2. float
3. char
4. boolean
5. String
JDBC Equivalent Datatype
Types.INTEGER
Types.FLOAT
Types.CHAR
Types.BOOLEAN
Types.VARCHAR
Database Datatype
number(7)
number(7,2)
char
-------------Varchar2
Netbeans IDE:
Vendor: SUN Micro system
Version : 6.7,7.0 also
Source code: open source
Download: www.netbeans.com
No additional settings required
Metadata: Data about Data is known as Metadata. In JDBC Programming Metadata concept
disvided into three types they are
i)
Database Metadata
ii)
ResultSet Metadata
iii)
Parameter Metadata.
1. Database Metadata: Database Metadata always deals with underline Database (Type of
Database we use) it deals universal Database details. Some of the Universal Database
details are
a) Finding the Database product name.
b) Finding the Database product version
c) Finding the Database product major version
d) Finding the Database product minor version
e) Finding the name of driver
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f) Finding the Driver major version
g) Finding the Driver minor version.
In order to find Database Metadata we need to create an Object java.sql.Database
Metadata. Database Metadata details can be obtained when the connection Object is
successfully created. To create an Object of Database Metadata we use the following
method which is present in Connection interface.
Java.sql.Connection
Public Database Metadata getMetadata
EX: Database Metadata dmd.con.getMetadata
Methods in Database Metadata interface:
i.
Public String getDatabase productName()
ii.
Public String getDatabaseProductVersion()
iii.
Public String getDatabaseProductMajorVersion()
iv.
Public String getDatabaseMinorVersion
v.
Public String getDriverName()
vi.
Public String getDriverVersion()
vii.
Public String getDriverMajorVersion()
viii. Public String getDriverMinorVersion()
P) Write a Java program which illustrates the concept of Database Metadata.
import java.sql.*;
class frt
{
public static void main(String args[])throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
DatabaseMetaData dm=con.getMetaData();
System.out.println("Database Product name is="+dm.getDatabaseProductName());
System.out.println("Database Product Versio="+dm.getDatabaseProductVersion());
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System.out.println("Driver Name="+dm.getDriverName());
System.out.println("Driver Version="+dm.getDriverVersion());
System.out.println("Driver Major Version="+dm.getDriverMajorVersion());
System.out.println("Driver Minor Version="+dm.getDriverMinorVersion());
}
}
/*OUTPUT
Database Product name is=Oracle
Database Product Versio=Oracle Database 10g Enterprise Edition Release 10.2.0.1.
0 - Production
With the Partitioning, OLAP and Data Mining options
Driver Name=Oracle JDBC driver
Driver Version=10.2.0.1.0
Driver Major Version=10
Driver Minor Version=2
*/
2. ResultSet metadata: ResultSet metadata always deals with user defined Databased(emp,
dept, student e.t.c.,) or deals with details about tables which are created in universal Database
details about table are nothing but
1.
2.
3.
4.
Finding the name of a table by passing the columns present in a table.
Finding the column types of Database and equivalent JDBC type
Finding the display size of the column name.
Finding the column names e.t.c.,
ResultSet metadata details we must create an Object details of java metadata. ResultSet
metadata details can be obtained when ResultSet Object is created because it contains details
about the table.
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ResultSet rs=st.executeQuery(“select * from dept”);
In order to create an Object of ResultSet Metadata we use the following method which is
present in ResultSet interface.
ResultSet
ResultSet Metadata getMetadata()
EX: ResultSetMetaData rsmd=rs.getMetaData()
1) Public int getColumnCount():This method is used for obtaining total number of
columns which are present in a table.
2) Public String getColumnName(int):
3) Public String getColumnLablel(int):
These methods are used for obtaining column
name of the Database by passing column number(Starts from 1,2,-----,n)
4) Public int getColumnType(int): This method is used for obtaining JDBC equivalent
type of Database column name by passing column number.
5) Public String getColumnTypeName(int): This method is used for obtaining Database
Datatype of that particular column by passing column number.
6) Public int getColumnDisplaySize(int): Which will display the column displaying size.
P) Write a JDBC application which illustrates the concept of ResultSet Metadata.
Hint: To execute any DDL statement we use the execute () of Statement interface.
import java.sql.*;
import java.util.*;
class Jdbcex2
{
public static void main(String args[])throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Driver loaded");
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Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from "+args[0]);
ResultSetMetaData rsmd=rs.getMetaData();
int noc=rsmd.getColumnCount();
System.out.println("number of columns="+noc);
for(int i=1;i<=noc;i++)
{
String cname=rsmd.getColumnName(i);
String dtype=rsmd.getColumnTypeName(i);
int jdbctype=rsmd.getColumnType(i);
int size=rsmd.getColumnDisplaySize(i);
System.out.println(cname+" "+dtype+" "+jdbctype+" "+size);
}
rs.close();
con.close();
}
}
P) Write a JDBC application which will display complete table that is records with Column
names.
import java.sql.*;
import java.util.*;
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class Jdbcex2
{
public static void main(String args[])throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Driver loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from "+args[0]);
ResultSetMetaData rsmd=rs.getMetaData();
int noc=rsmd.getColumnCount();
System.out.println("------------------");
for(int i=1;i<=noc;i++)
{
System.out.println(rsmd.getColumnName(i)+" ");
}
System.out.println("\n");
System.out.println("-------------------");
//printing records
while(rs.next())
{
for(int i=1;i<=noc;i++)
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{
String s1=rs.getString(i);
System.out.println(s1+" ");
}
System.out.println("\n");
}
rs.close();
st.close();
con.close();
}
}
3. Parameter MetaData: Parameter MetaData always deals with information about
indexed/positional parameters such as
a) Number of Positional Parameters.
b) Number of input parameters
c) Number of output parameters
d) Input and Output parameter types of both JDBC equivalent and Database equivalent.
1. As on today most of the popular Database products are not supporting parameter Metadata
because positional parameters decided by the Java programmer and specifying their types while
executing dynamic queries and stored procedures.
2. But as on today the CloudSpace Organization developed Database called CloudSpace
Database which will support parameter Metadata.
3. In order to get Parameter MetaData we need to create an Object of java.sql.ParameterMetadata
interface. To create an Object of parameter MetaData we use the following method which is
present in PreparedStatement interface and it is further inherited into CallableStatement.
Public parameterMetaData getParameterMetaData()
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Parameter pmd=ps.getParameterMetadata()
parameterMetaData pmd=cs.getParameterMetaData();
Q) can we execute any select query without execute query?
A) Yes, We can execute any select query by using the following methods.
Java.sql.Statement
Public boolean String(String)
Java.sql.PrepatedStatement
Public boolean execute()
 Dynamic select query
After executing either static select query or dynamic select query successfully the result of the
Database table is available in the main memory without having any name.
If at all we are giving the name to unnamed result then it must be an Object of ResultSet
interface and it can be given by calling a method called getResultSet() and whose prototype
java.sql.Statement
Public ResultSet getResultSet
Statement st=con.createStatement();
st.execute(“select * from dept”);
ResultSet rs=st.getResultSet();
PreparedStatement ps=con.PrepareStatement(“select * from dept”);
ps.execute();
ResultSet rs=ps.getResultSet()
P) Write a JDBC application which will execute any DDL querry.
import java.sql.*;
import java.util.*;
class Jdbcex6
{
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public static void main(String args[]) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Drivers loaded");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
System.out.println("Connection Obtained from Oracle");
Statement st=con.createStatement();
Scanner s=new Scanner(System.in);
System.out.println("Enter DDL Statement");
String s1=s.nextLine();
st.execute(s1);
System.out.println("DDL Execute- veriy in Oracle");
st.close();
con.close();
}
}
Advantages of Type-4 Drivers:
1. Type-4 drivers implemented by Database vendors in Java language so that they are
always possessing platform independency.
2. Type-4 driver takes less number of two and pro calls between Java application and
Database software so that network traffic flow is reduced it leads to high performance.
3. This driver is always recommended by the industry for developing large scale Database
applications.
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Disadvantages:
1. Type-4 driver allows developing only two tier applications but not 3 tier applications.
2. While we are using Type-4 drivers the Java programmer must ensure related jar files
must be installed in the client machine.
Type-2 Drivers:
Advantages:
1.
2.
3.
4.
Type-2 Drivers developed by Database vendors.
The implementation language of Type-2 driver is mixture of Java and C.
Hence Type-2 drivers always possess partial platform independency.
Type-2 drivers are also known as native drivers and Type-2 drivers are highly
recommended to develop small scale Database applications or standalone applications.
Disadvantages:
1. Possesses partial platform independency but not complete platform independency(like
Type-4)
2. With Type-2 driver we are able to develop 2 tier applications but not 3 tier applications.
Summary of Type-2 driver:
(Oracle Corporation)
Driver Name
: OracleDriver
Fully Qualified Name : oracle.jdbc.driver.*
Logical Name
: oci8
Vendor
: Oracle Corporation
Jar files
: Classes12.jar
Ojdbc.jar
Loading Type-2 Driver:
EX: DriverManager.registerDriver(“new oracle.jdbc.driver.OracleDriver”) //explicit
Class.forName(“oracle.jdbc.driver.OracleDriver”) //implicit
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Obtaining the connection from the Database by using Type-2 Driver:
Syn: Main protocol : sub protocol : Logical name of Type-2: @service id
EX: jdbc: oracle : oci8 : @ orcl
Connection con=DriverManager.getConnection(“jdbc:oracle:oci8:@sathya”,”scott”,”tiger”)
P) Write a JDBC application which will execute all the group functions in Oracle by using
Type-2 Driver.
import java.sql.*;
import java.util.*;
class Jdbcex6
{
public static void main(String args[]) throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Drivers loaded");
Connection con=DriverManager.getConnection("jdbc:oracle:oci8:@orcl","scott","tiger");
System.out.println("Connection Obtained from Oracle");
Statement st=con.createStatement();
ResultSet
rs=st.executeQuery("select
sum(sal),avg(sal),min(sal),max(sal),count(*),count(sal),count(distinct sal)"
+ " from emp");
if(rs.next())
{
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System.out.println("total sal="+rs.getFloat(1));
System.out.println("average sal="+rs.getFloat(2));
System.out.println("maximum sal="+rs.getFloat(3));
System.out.println("minimum sal="+rs.getFloat(4));
System.out.println("Total number of employees="+rs.getInt(5));
System.out.println("Total number of employees salary exluding nulls="+rs.getInt(6));
System.out.println("Total
duplicates="+rs.getInt(7));
number
of
employees
salary
}
rs.close();
con.close();
}
}
/*OUTPUT
Drivers loaded
Connection Obtained from Oracle
total sal=140990.52
average sal=11749.21
maximum sal=11749.21
minimum sal=11749.21
Total number of employees=12
Total number of employees salary exluding nulls=12
Total number of employees salary exluding nulls and duplicates=1
*/
84
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Application Layer
Database Layer
Java Application
Database Software
1
JDBC API
4
7
6
2
T
y
p
e
2
5 5
5
3
Advantages:
1. We know that Type-2 driver implementation is the mixture of java and C
2. Hence it possess partial platform independency(far better than Type-1)
3. With Type-2 driver we get less number of to and pro calls and reduces network traffic
flow and improves the performance.
4. Highly recommended to perform standalone Database operations.
Disadvantages:
1. Possesses platform independency but not complete platform independency(like Type-4)
2. With Type-2 driver we are able to develop 2 tier applications but not 3 tier applications.
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Summary of JDBC drivers:
JDBC Driver Type
Name
Vendor
Type-1
JbdcOdbc
Driver
Type-2
Native
Database Vendors
Java+C
Type-3
Net protocol
Server Vendors
Java
Type-4
All Java, pure, thin
Database Vendors
Java
Bridge SUN Micro System
Implementation
Language
C
NOTE: All the applications upto now we have done are JDBC 2.0 from upcoming applications
are JDBC 2.1 to 3.0
NOTE2: Save point is JDBC 4.0 application.
Batch Processing in JDBC: It is one of the additional facility introduced in JDBC2.1 version.
Batch processing always makes us to get consistent results.
Need of Batch Processing: We know that whatever the queries we execute by default with a
JDBC application, it is by default executed and auto committed. If we develop group of
dependent transactions(queries) then those group of queries are individually visiting from Java
application to Database software and there is a possibility of executing some of the transactions
are not executed successfully because of this execution we can figure out(identify) the following
limitations.
1. There is a possibility of leading inconsistent Database results.
2. Because of individual query execution, to and pro calls are more between Java
application and Database software. So that network traffic flow is more and we get lesser
performance.
3. Because of individual query execution, it may take more execution time. To solve the
above problems we must use the concept of Batch processing.
Advantages of Batch Processing:
1. It always provides and ensures consistent results of the Database.
2. To an Pro calls are minimized(takes only 2 To and Pro calls)
3. It provides less execution time because all dependent and independent transactions are
put in the batch.
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Def: The process of combining or grouping different type or similar type of DML statements in a
single unit and executing in the Database software is known as Batch Processing. While we are
executing both DML statements, there is a possibility of getting BatchUpdateException.
When we get BatchUpdateException: BatchUpdateException is one the predefined sub
exception of java.sql.SQLException whenever we submit n number of dependent transactions to
the Database in the form of a batch and assume n-1 transactions are successfully executed and
nth transaction is unable to execute because of network problems or Database problems then
JVM rises a predefined exception called java.sql.BatchUpdateException with respective nth
transaction which is unable to execute. If BatchUpdateException is generated then as
rollback(undoing the changes to the original values). If no BatchupdateExcepion is coming then
as a Java programmer we commit(doing the Changes to the Original Database). Batch Processing
concept always deals with DML statements only but not DDL Statements.
Steps for developing Batch Processing applications:
1. Begin the transaction by making auto commit as false(recommended and mandatory) to
make auto commit as false we use the following method present in connection interface.
java.sql.Connection
public void setAutoCommit(boolean)
EX: con.setAutoCommit(flase)
This statement makes the Database environment to understand postpone the commitment of
transaction execution until we say auto commit as true.
2. To start with Batch processing we need to create an Object of Statement interface.
EX: Statement st=con.creaeStatement();
3. Decide the group of dependent/individual DML statements and put them in a batch. To
make the DML statements as batch we use the following method present in Statement
interface.
java.sql.Statement
public void addBatch(String)
Here String parameter represents DML statements(insert,update,delete).
EX: st.addBatch(Update Account set bal=sal+1000 where accno=502”)
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st.addBatch(Update Account set bal=3000 where accno=503”);
st.addBatch(“delete from dept”);
4. Execute batch of Statements to execute the batch of statements we use the following
method which is present in statement interface.
Java.sql.Statement
public int[] executeBatch()
Array of integers the number of records affected individually in the Database software
because of Database software.
EX: int res=st.executeBatch()
res
0
1
1
2
3
2
4
3
In order to find total number of records affected in the original Database because of
Batch execution can be found by using following code segment.
int s=0;
{
s=s+res[i];
System.out.println(“number of records affected in oiginal Database =”+s); //6
}
Note: During the batch execution if one of the Statement is not executing because of
condition is not satisfying then its result in the int[] is 0. It is not treated as BatchUpdat
dExcception.
5. If BatchUpdateException is resulted then perform step-6 otherwise perform step-7
6. Rollback the changes to do this use the following method which is present in Connection
interface.
java.sql.Conenction
public void rollback
EX: con.rollback()
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7. Since no BatchUpdateException is rise, as a Java programmer first we need to set auto
commit as true and call commit() which is present in Connecton interface
EX: con.setAutoCommit(true)
Con.commit();
P) Write a Java program which illustrates Batch Processing?
import java.sql.*;
import java.util.*;
class Jdbcex6
{
public static void main(String args[])
{
Connection con=null;
Statement st=null;
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
con.setAutoCommit(false);
st=con.createStatement();
st.addBatch("insert into student10 values(43,'doni')");
st.addBatch("insert into student10 values(32,'Kiran')");
int res[]=st.executeBatch();
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int s=0;
for(int i=0;i<res.length;i++)
{
s=s+res[i];
}
System.out.println("number of rows affected="+s);
con.setAutoCommit(true);
con.commit();
}
catch(BatchUpdateException be)
{
System.err.println("Problem in batch execution");
try
{
con.rollback();
}
catch(SQLException se)
{
System.err.println("Database connections are not follwed");
}
}
catch(ClassNotFoundException ce)
{
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System.err.println("Class not available");
}
catch(SQLException se)
{
System.err.println("Database connections are not followed");
}
finally
{
try
{
st.close();
con.close();
}
catch(SQLException se)
{
System.err.println("Database connections not followed");
}
}
}
}
Q) Can we write Try and Catch blocks in Catch and Finally blocks?
A) Yes, In Catch and Finally blocks whenever we refer the Objects of class and interfaces in
which are throwing the exceptions then such type of Objects must be always placed in within Try
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and Catch blocks. Specially all the interfaces java.sql.* package (Connection, statement,
PreparedStatement, ResultSet, e.t.c.,) are throwing the predefined exception called java.sql.SQL
Exception. Hence we are referring these interface Objects either in Catch block or in finally
block, those Objects must be written in try and catch blocks otherwise we will get Compile tine
error.
Q) What are the reasons for rising Batch?
BatchUpdateExcception is rising because of the following conditions.
a) Because of Database Software problems/failure when batch statements are executing.
b) Because of Network problems implementing the following problem by using Batch
Processing.
Q) Why Callable Statement is not useful for executing Batch Applications?
A) CallableStatement is meant for executing stored procedures resides in Database software with
collection of DML Statements.
P) Write above JDBC program to insert four records by using PreparedStatement.
NOTE: By using PreparedStatement we can perform once one DML operation for suppose if we
would like to insert four records we can insert but here we would like to update records that is
not possible. We can update separately that means in separate PreparedStatement Object because
PreparedStatement never participate repeatedly in parsing, compilation phase.
import java.sql.*;
import java.util.*;
class jdbc90
{
public static void main(String args[])
{
Connection con=null;
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PreparedStatement ps=null;
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
con.setAutoCommit(false);
ps=con.prepareStatement("insert into student10 values(?,?)");
ps.setInt(1,22);
ps.setString(2,"king");
ps.addBatch();
ps.setInt(1,23);
ps.setString(2,"ring");
ps.addBatch();
ps.setInt(1,73);
ps.setString(2,"sing");
ps.addBatch();
ps.setInt(1,73);
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ps.setString(2,"zing");
ps.addBatch();
int res[]=ps.executeBatch();
if(res.length>-1)
{
System.out.println("Number of rows inserted="+res.length);
}
con.setAutoCommit(true);
con.commit();
}
catch(BatchUpdateException be)
{
System.err.println("Problem in batch execution");
try
{
con.rollback();
}
catch(SQLException se)
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{
System.err.println("Database connections are not follwed");
}
}
catch(ClassNotFoundException ce)
{
System.err.println("Class not available");
}
catch(SQLException se)
{
System.err.println("Database connections are not followed");
}
finally
{
try
{
ps.close();
con.close();
}
catch(SQLException se)
{
System.err.println("Database connections not followed");
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}
}
}
}
P) Write a JDBC Batch Processing program by using following Tables.
Acno
10
20
Name
Sathya
Ravi
Balance
90000
20000
Acno
30
40
Name
Raju
Sathya
Balance
40000
60000
a) Transfering `2000 from Sathya Account to Raju Account
b) Transfer `2000 from Sathya to Ravi.
import java.sql.*;
class jdbc90
{
public static void main(String args[])
{
Connection con=null;
PreparedStatement ps1=null;
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PreparedStatement ps2=null;
PreparedStatement ps3=null;
PreparedStatement ps4=null;
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
con.setAutoCommit(false);
ps1=con.prepareStatement("update acctran1 set bal=bal+2000 where accno=?");
ps1.setInt(1,30);
ps1.addBatch();
ps2=con.prepareStatement("update acctran1 set bal=bal-2000 where accno=?");
ps2.setInt(1,40);
ps2.addBatch();
ps3=con.prepareStatement("update acctran set bal=bal+2000 where accno=?");
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ps3.setInt(1,20);
ps3.addBatch();
ps4=con.prepareStatement("update acctran set bal=bal-2000 where accno=?");
ps4.setInt(1,10);
ps4.addBatch();
int res1[]=ps1.executeBatch();
int res2[]=ps2.executeBatch();
int res3[]=ps3.executeBatch();
int res4[]=ps4.executeBatch();
con.setAutoCommit(true);
con.commit();
}
catch(BatchUpdateException be)
{
System.err.println("Problem in batch execution");
try
{
con.rollback();
}
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catch(SQLException se)
{
System.err.println("Database connections are not follwed");
}
}
catch(ClassNotFoundException ce)
{
System.err.println("Class not available");
}
catch(SQLException se)
{
System.err.println("Database connections are not followed");
}
finally
{
try
{
ps1.close();
ps2.close();
ps3.close();
ps4.close();
con.close();
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}
catch(SQLException se)
{
System.err.println("Database connections not followed");
}
}
}
}
Developing Flexible applications: If we write any JDBC application with specific driver url,
username and password then that JDBC application communicates with a specific Database as
and when any changes has taken place in Database software it is mandatory for the JDBC
programmer to do the corresponding changes even in Java program such type of JDBC
application development is known as flexible application hard coded approach other words if we
write any JDBC application by specifying fixed technical information of Database(Driver name,
url, user name and password) then that application is known as hard coded approach.
Drawbacks with Hard Coded Approach:
1. Takes more time to do the changes in the source code of JDBC applications.
2. It kills software development that takes more amount of time there is a possibility of
getting inconsistent results because the current changes of Database to be taken place in
all the JDBC applications otherwise inconsistency problems will be arises.
3. The above problems can be eliminated by an approach of flexible application
development.
4. Flexible application development makes us to understand if we change in one place about
the technical information of Database those changes reflects in all the JDBC applications
without changing source code the following diagram give the overview of flexible
application development.
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oracle
7
1
2
Database property
Driver= oracle:jdbc:odbc:OracleDriver
Java application
DB2
url=jdbc:oracle:thin:@localhost:1521:orcl
7
uname: scott
pwd : tiger
4
MySql
7
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SQL
Server
6
8
Properties file: Properties file is one in which the data is organizing in the form of (key, value).
EX: Student.prop/student.rbf
Student no
Sname
Marks
=1000
=Sathya
==99.9
Here (student no, sname, marks) are called keys or properties names, (1000,Sathya, 99.99) are
called values. Property files always resides in secondary memory and it must be saved some file
name with an extension .prop or .rbd
Steps for reading the data form properties file:
1. Ensure that properties file must be created first in the text editors.(We know that
properties files always resides in secondary memory)
2. Open the properties file in read mode by making use of FileInputStream class
EX: FileInputStream fis=new FileInputStream(“db.prop”)
3. Create an Object of properties class. Properties is one of the predefined file present in
java.util.* package and the class Object is used for obtaining the data of the properties
file into main memory.
EX: Properties p=new Properties();
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p
Key, value
Here p resides in heap memory
4. Load or transfer the content of Properties file into Properties class Object (from
secondary memory into primary memory) I order to load the content of Properties file
into the Properties class Object we use following methods present in Properties class.
java.util.Propeties
public void load(FileInputSteam)
p.load(fis)
Obtain values(Property values) to get the property values by passing the Property names, we
use the following method.
java.util.properties
public String getProperty(String)
pvalue
pname
(value)
(key)
EX: String dname=p.getProperty(“driver name”)
String url=p.getProperty(“url”)
String uname = p.getProperty(“uname”)
5. Use property values which are obtained in step-5 in JDBC application to communicate
with any Database.
6. Close the Properties file which was opened in Step-2.
EX: fis.close()
P) Write a JDBC application to communicate with a specified Database.
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Connection.prop containis
driver = oracle.jdbc.driver.OracleDriver
url
= jdbc:oracle:thin:@localhost:1521:orcl
uname = scott
pwd
= tiger
tname = select * from emp
import java.util.*;
import java.io.*;
import java.sql.*;
class jdbc90
{
public static void main(String args[])
{
try
{
Properties p=new Properties();
FileInputStream fis=new FileInputStream(args[0]);
p.load(fis);
String driver=p.getProperty("driver");
String url=p.getProperty("url");
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String uname=p.getProperty("uname");
String pwd=p.getProperty("pwd");
Class.forName(driver);
Connection con=DriverManager.getConnection(url,uname,pwd);
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from emp");
while(rs.next())
{
String empno=rs.getString(1);
String job=rs.getString(2);
String mgr=rs.getString(3);
System.out.println(empno+" "+job+" "+mgr);
}
st.close();
con.close();
}
catch(FileNotFoundException fe)
{
System.err.println("File not available");
}
catch(ArrayIndexOutOfBoundsException ae)
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{
System.err.println("Please enter file properties file");
}
catch(ClassNotFoundException ce)
{
System.out.println("Class is not available");
}
catch(SQLException se)
{
System.err.println("Connections are not followed");
}
catch(Exception e)
{
System.err.println(e.getMessage());
e.printStackTrace();
}
}
}
Note: Industry always recommended developing all the JDBC related applications with flexible
approach but not with hard coded approach.
Observation: To perform any flexible application we have to use Class.forName() otherwise we
will get compile time error.
Types of ResultSet: ResultSet is one of the predefined interface present in java.sql.* package
and whose Object is used for holding the number of records return by the select query. We know
that ResultSet interface Object can be obtained in three ways they are
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1. executeQuery(-) of Statement interface.
EX: ResultSet rs=st.executeQuery(“select * from dept”);
2. executeQuery() of PreparedStatement.
EX: PreparedStatement ps=con.prepareStatement(“select * from dept”);
ResultSet rs=ps.executeQuery();
3. execute() of both Statement and PreparedStatement interfaces.
EX: st.execute(“select * from dept”);
ResultSet rs=st.getResultSet();
PreparedStatement ps=con.prepareStatement(“select * from dept”);
ps.execute();
ResultSet rs=ps.getResultSet();
All these ResultSet interface Objects are allowing to retrieve data only in forward direction
but not in backward direction and such ResultSets are known as non scrollable ResultSets.
Which are available in JDBC2.0 based on direction of retrieval and modification as part of JDBC
2.2 ResultSets are classified into four types they are
1.
2.
3.
4.
1.
Non- Scrollable ResultSets
Scrollable ResultSets
Read-only ResultSets
Updatable ResultSets
Non-Scrollable ResultSets: A non scrollable ResultSet allows us to retrieve the records
in forward direction but not in backward direction and random retrieval.
2. Scrollable ResultSet: Scrollable ResultSet allows us to retrieve the records either in
forward or backward direction
3. Read-only ResultSet: Read-only ResultSets are those whose changes never taken place
but original Database changes occurs in ResultSet.
4. Updatable ResultSet: Updatable ResultSets are those which objects are permitting to
have the changes both in ResultSet and Database that is whatever the changes we do in
ResultSet that are reflecting to original Database and original Database changes are
reflecting to ResultSet hence both ReadOnlyResultSets and UpdatableResultSets are
treated as scrollable ResultSets.
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In order to develop non scrollable, scrollable, Readonly, Updatable ResultSets are use the
following datamembers present in java.sqi.ResultSet interface.
Data members:
1. Public static final int TYPE-FORWARD_ONLY
2. Public static final int TYPE_SCROLL_INSENSITIVE
3. Public static final int TYPE_SCROLL_SENSITIVE Here these Datamembers are
called mode value.
4. Public static final int CONCUR_READ_ONLY
5. Public static final int CONCUR_UPDATABLE
Here these Datamembers are
called concur value.
The default data members are 1 and 4.
1. Public static final int TYPE-FORWARD_ONLY: This datamember allows us to
retrieve the data from ResultSet only in forward direction.
2. Public static final int TYPE-SCROLL_INSENSITIVE: This datamember represents
modifications of ResultSet object. It never occur in Original Database.
3. Public static final int TYPE_SCROLL_SENSITIVE: This datamember represents
changes of ResultSet permitted to occur in the original Database.
4. Public static final int CONCUR_READ_ONLY: This datamember represents Database
never permits changes of ResultSet object.
5. Public static final int CONCUR_UPDATABLE: This datamember represents Database
permits to have changes of ResultSet Object.
1. Write a Statement to create non-scrollable ResultSet
EX: Statement st=con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet
CONCUR_READ_ONLY)
ResultSet rs=st.executeQuery(“select * from emp”);
Here rs represents non scrollbale ResultSet.
2. Write a Statement for Preparing ReadOnlyResultSet
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EX:
Statement st=con.createStatement(ResultSet
ResultSet, CONCUR_READ_ONLY)
TYPE_SCROLL_INSENSITIVE,
ResultSet rs=st.executeQuery(“select * from emp”);
Here rs is representing Read only ResultSet.
3. Write a Statement for UpdatableResultSet
EX: Statement st=con.createStatement(ResultSet TYPE_SCROLL_SENSITIVE, ResultSet
CONCUR_UPDATE)
ResultSet rs=st.executeQuery(“select * from emp”);
Here rs is called UpdatableResultSet
The above 2 and 3 statements are comes under even scrollable ResultSets. Connection
interface contains the following method to prepare an appropriate type of ResultSet interface
Object.
public statement CreateStatement(int mode, int Concurrency)
mode represents 1,2,3 datamembers, concurrency represents 4,5 datamembers.
Methods in ResultSet interface in JDBC 2.1:
1. public boolean previous()
2. public void first()
3. public void last()
4. public boolean isFirst()
5. public boolean isLast()
6. public void beforeFirst()
7. public void afterLast()
8. public boolean isBeforeFirst()
9. public boolean isAfterLast()
10. public int getRow()
11. public void absolute(int)
12. pubic void relative(int)
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1. public boolean previous(): this method returns true provided ResultSet interface Object
is having previous record it will be presenting to previous record. If no more records
available it returns false.
2. public void first()
3. public void last()
These methods are used for making the ResultSet interface
Object pointing to the first and last record respectively.
EX: res.first()
res.last()
4. public boolean isFirst()
5. public boolean isLast()
These methods are used for checking whether the ResultSet
object is pointing first or last records in other words method4 and 5 returns true provided
ResultSet interface Object is pointing to first and last records respectively. Otherwise it
returns false.
EX: rs.first()
boolean b1=rs.isFirst()
System.out.println(b1) //true
b1=rs.isLast()
System.out.println(b1); //false
EX2: rs.last()
boolean b1=rs.isFirst();
System.out.println(b1); //false
b1=rs.isLast()
System.out.println(b1); //true
6. public void beforeFirst()
7. public void afterLast()
These methods are used for making the ResultSet object
pointing to either before first or afterLast for retrieving the records either in forward or
backward direction.
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8. public boolean isBeforeFirst()
9. public boolean isAfterLast()
These methods returns true provided ResultSet
interface is pointing either before first or after last respectively. Otherwise methods
returns false.
EX: rs.beforeFirst(); //by default
boolean b1=rs.isBeforeFirst()
System.out.println(b1); //false
rs.afterLast()
boolean b1=rs.isBeforeFirst()
System.out.println(b1); //false
b1=rs.isAfterLast()
System.out.println(b1); //true
10. public int getRow(): This method is used for obtaining the record number where
ResultSet interface object is pointing.
11. public void absolute(int): This method is used for making the ResultSet object to point
to a particular record by visiting either forward direction or backward direction depends
on type of int value we enter. If int value is positive then ResultSet interface object
moves in forward direction with respective to first record. If int value negative then
ResultSet interface object moves in backward direction with respect to last record.
12. pubic void relative(int): This method is used for making the ResultSet interface object
to a specific record by moving forward direction or backward direction with respective to
current record depends on type of int value. If int value is positive then ResultSet object
moves in forward direction with respective to current record. If int value is negative then
ResultSet interface Object moves in backward direction with respect to record. While we
are applying methods 11 and 12 the ResultSet object must point to the record area.
P) Write a JDBC application which will print the records of a table both in forward
direction and backward direction and in Random retrieval.
import java.sql.*;
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import java.util.*;
class Jdbcex61
{
public static void main(String args[])throws Exception
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
Statement
st=con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_READ_ONLY);
ResultSet rs=st.executeQuery("Select * from emp");
System.out.println("Forward Direction");
System.out.println("-----------------");
while(rs.next())
{
System.out.println(rs.getString(1)+" "+rs.getString(2));
}
rs.afterLast();
while(rs.previous())
{
System.out.println(rs.getString(1)+" "+rs.getString(2));
}
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System.out.println("-------------------------------------");
rs.first();//rs print first record
System.out.println(rs.getString(1)+" "+rs.getString(2));
rs.absolute(4); //respective to fourth record.
System.out.println(rs.getString(1)+" "+rs.getString(2));
rs.relative(3); //rs points sevent record
System.out.println(rs.getString(1)+" "+rs.getString(2));
rs.getString(2);
rs.relative(-2); //rs points 5th (7-2) record
System.out.println(rs.getString(1)+" "+rs.getString(2));
rs.last(); //rs points last record that is 14 th
System.out.println(rs.getString(1)+" "+rs.getString(2));
rs.relative(-4);
System.out.println(rs.getString(1)+" "+rs.getString(2));
rs.last();
rs.absolute(-4);
System.out.println(rs.getRow());
rs.close();
st.close();
con.close();
}
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}
/*OUTPUT
Forward Direction
----------------7788 CLERK
101 null
7499 SALESMAN
7521 SALESMAN
7566 MANAGER
7654 SALESMAN
7698 MANAGER
7782 MANAGER
7839 PRESIDENT
7844 SALESMAN
7900 CLERK
7902 ANALYST
7902 ANALYST
7900 CLERK
7844 SALESMAN
7839 PRESIDENT
7782 MANAGER
7698 MANAGER
7654 SALESMAN
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7566 MANAGER
7521 SALESMAN
7499 SALESMAN
101 null
7788 CLERK
------------------------------------7788 CLERK
7521 SALESMAN
7698 MANAGER
7566 MANAGER
7902 ANALYST
7782 MANAGER
9 */
Updatable ResultSet: Updatable ResultSets are those in which original Database modifications
are reflected to ResultSet Object and ResultSet objects modifications are reflected in original
Database.
Q) How do you insert a record, delete a record and update a record of any Database
without using SQL queries.
We can do the above Database operations by making use of Updatable ResultSets.
NOTE: Scorollable ResultSet fecility support by all types of JDBC drivers Updatable
ResultSets are supported by Type-1 driver(SUN Micro System) and other drivers Type-2, Type3, Type-4 are not supported.
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Methods present in ResultSet interface for supporting Updatable ResultSet:
1.
2.
3.
4.
5.
1.
public void moveToInsertRow()
public void UpdateXxx(int colon,xxx value)
public void insertRow()
public void deleteRow()
public voiud UpdateRow()
public void moveToInsertRow(): This method is used for creating an empty record cell
int the ResultSet interface object that is a buffer will be creating for inserting a new
record into the original Database.
rs.moveToInsertRow()
2. public void UpdateXxx(int colon,xxx value): This method is one of the generalized
method for updating the values in the ResultSet object. Here Xxx represents any
fundamental datatype and date.
3. public void insertRow(): This method is used for inserting the record of ResultSet into
the original Database.
4. public void deleteRow():
5. public voiud UpdateRow():
These methods are used for deleting a record from
ResultSet and same record will be deleted from original Database and also update values
of ResultSet and they interns updates the original Database values.
Steps for inserting a record into the original Database through the UpdateResultSet:
1. Call moveToInsertRow() for creating an empty buffer in ResultSet object.
EX: rs.moveToInsertRow()
rs
Deptno
10
20
30
40
Dname
Fin
HR
MAR
ACC
Loc
HYD
MUM
BAN
CHN
--------------------------------------------------------------------------------------------------------------------rs.moveToInsertRow()
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2. Update the column values in the ResultSet by calling UpdateXxx()
EX: rs.UpdateInt(1,50)
rs.UpdateString(2,”production”)
rs.UpdateString(3,”Hyd”).
rs
Deptno
10
20
30
40
50
Dname
FIN
HR
MAR
ACC
PROD
Loc
HYD
MUM
BAN
CHN
VJY
--------------------------------------------------------------------------------------------------------------------rs.moveToInsertRow()
Whatever the record is marked for insertion in ResultSet object, insert into the original Database
EX: rs.InsertRow()
P) Write a JDBC program which will insert a record in the dept Database by using
UpdateResultSet.
import java.sql.*;
import java.util.*;
class Jdbcinsert
{
public static void main(String args[])throws Exception
{
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Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con=DriverManager.getConnection("jdbc:odbc:siva","scott","tiger");
Statement
st=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDAT
ABLE);
ResultSet rs=st.executeQuery("select * from student5");
//step-1
rs.moveToInsertRow();
//step-2
Scanner s=new Scanner(System.in);
System.out.println("enter sno");
int sno=Integer.parseInt(s.nextLine());
System.out.println("enter name");
String name=s.nextLine();
System.out.println("Enter gender");
String gender=s.nextLine();
rs.updateInt(1,sno);
rs.updateString(2,name);
rs.updateString(3,gender);
//step-3
rs.insertRow();
System.out.println("Record inserted");
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rs=st.executeQuery("select * from student5");
while(rs.next())
{
System.out.println(rs.getString(1)+" "+rs.getString(2));
}
rs.close();
st.close();
con.close();
}
}
Observations;
1.
2.
3.
4.
These programs may execute may not execute.
It is not possible to do modifications directly on Database operations.
We should use Type-1 Drivers only.
There is a chance to give irrelevant output.
Steps for deleting a record from the original Database through ResultSet Object:
1. Decide which record we want to remove and make ResultSet object to point
rs.absolute(2); //rs points to second record
2. Call the DeleteRow method for marking the record to delete in the ResultSet object the
same method will be removed form the original Database
EX: rs.deleteRow
P) Write a JDBC program for deleting record from the original Database through
ResultSet Object.
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import java.sql.*;
import java.util.*;
class Jdbcdelete
{
public static void main(String args[])throws Exception
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
//Step-2
Connection con=DriverManager.getConnection("jdbc:odbc:siva","scott","tiger");
Statement
st=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDAT
ABLE);
ResultSet rs=st.executeQuery("select * from student5");
//step-1
Scanner s=new Scanner(System.in);
System.out.println("enter record number to delete");
int sno=Integer.parseInt(s.nextLine());
//step-2
rs.deleteRow();
System.out.println("Record deleted sucessfully");
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rs=st.executeQuery("select * from student5");
while(rs.next())
{
System.out.println(rs.getString(1)+" "+rs.getString(2));
}
rs.close();
st.close();
con.close();
}
}
Note: It is not possible to update Database original records by using UpdateResultSet we can
update, delete only records which are inserted by ResultSet update.
Steps for updating a record of Original Database through ResultSet object
1. Decide which record values we want to update and make ResultSet object to point to that
record.
EX: rs.absolute(5); //rs points fifth record
2. Update the required values of the specified record in step-1 by calling UpdateXxx(-)
EX: rs.updateSting(2,”production”)
Rs.updateSting(3,”Sales”);
3. Update the record of marked for updation of ResultSet into the original Database by
calling updateRow()
EX: rs.updateRow()
P) Write a JDBC program for updating a record of original Database through ResultSet
object.
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import java.sql.*;
import java.util.*;
class Jdbcupdate
{
public static void main(String args[])throws Exception
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver registered");
//Step-2
Connection con=DriverManager.getConnection("jdbc:odbc:siva","scott","tiger");
Statement
st=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDAT
ABLE);
ResultSet rs=st.executeQuery("select * from student5");
//step-1
Scanner s=new Scanner(System.in);
System.out.println("enter record number to update");
rs.absolute(1);
int sno=Integer.parseInt(s.nextLine());
//step-2
rs.updateString(2,"raju");
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rs.updateString(2,"vijay");
//step-3
rs.updateRow();
System.out.println("Record updated sucessfully");
rs=st.executeQuery("select * from student5");
while(rs.next())
{
System.out.println(rs.getString(1)+" "+rs.getString(2));
}
rs.close();
st.close();
con.close();
}
}
RowSets in JDBC 3.0:
1. RowSets are the distinct facility available JDBC 3.0 version. RowSet is the one of
specialization released by SUN Microsystem for getting some significant changes in
traditional JDBC programming.
2. We know that RowSet specification is nothing but set of rules given in the form of
abstract methods and placed in interfaces.
3. SUN Microsystem has developed a root interface called RowSet and it is present in a
predefine package called javax.sql.* in otherwords in order to deal with RowSets concept
in the JDBC programming, we must import a predefined package called javax.sql.*. This
package is an extension to java.sql.* while we are using RowSets in our JDBC
programming, we get the following significant advantages.
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i.
With the single object of RowSet we are able to complete all Database operations
RowSets transfers the data all at once between the multiple machines over the network
round trips are reduced and improved the performance.
ii. RowSet specification follows java bean properties (Java Bean is a class which contains
set of setXxx(-) and set of getXxx() because of Java Bean properties satisfaction the
programmer feel easy in remembering the methods.
iii. RowSet specification contains Event Delegation Model.
Types of RowSets: The concept of RowSet is classified into three types they are
I. Cached RowSet
II. JDBC RowSet
III. Web RowSet
All the above three are the predefined interfaces of RowSet interface and they found in a
predefined package called javax.sql.*.
I.
i.
ii.
iii.
Cached RowSet: Cached RowSet is one of the sub interface of RowSet. Cached
RowSet is one of the disconnected RowSet.
A Disconnected RowSet one which maintains the communication java application
and original Database for a limited span of time but not for a longtime that is after
retrieving the data form Database the connection will be disconnected form the
original database and as and when changes are occurring either in RowSet or in
database again connection will be obtained.
The cached RowSet interface implemented by Oracle corporation in the name of
OracleCachedRowSet which is present in a predefined package called
Oracle.Jdbc.RowSet.*
Programatically RowSet rs=new OracleCachedRowSet() or
CachedRowSet crs=new CachedRowSet()
Note: Even SUN Microsystem has developed an implementation class for CachedRowSet
interface known as SunCachedRowSet.
II.
JDBC RowSet:
1. JDBC RowSet is the sub interface of RowSet interface. JDBC RowSet interface object is
treated as connected RowSet. A connection RowSet is one which organizing a connection
permanently from staring of the application to ending of the application.
2. The interface JDBC RowSet implemented by Oracle corporation on the name of Oracle
JDBC RowSet and it is present in a predefined package called oracle.jdbc.RowSet.*.
Programatically RowSet rs=new OracleJdbcRowSet().
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Note: Even Sun Microsystem has provided the implementation JDBC RowSet interface on
the name of SunJdbcRowSet.
III.
i.
ii.
WebRowSet:
WebRowSet is one of the interface used in servlets and jsp for implementation of web
applications.
Oracle corporation has provided implementation for WebRowSet the name of
OracleWebRowSet present in oracle.jdbc.RowSet.* package.
Conclusion: While we are using OracleCachedRowSet and OracleWebRowSet we need to set
the classpath for both ocrs12.jar and ojdbc14.jar(in case of 9i) or ojdbc14.jar(in case of oracle
10g and higher versions)
Methods in RowSet interface:
1. public void setURL(String)
2. public void setUname(String)
3. public void setPassword(String)
4. public void setCommand(String)
5. public boolean execute()
6. public void setConcurrency(int)
7. public void setMode(int)
8. public String getURL()
9. public String getUsetName()
10. public String getPassword()
11. public String getCommand()
12. public int getConccurency();
13. public int getMode()
P) Write a Java program which illustrates the concept of CachedRowSets.
import java.sql.*;
import javax.sql.*;
import oracle.jdbc.rowset.*;
public class Jdbcex6
{
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public static void main(String args[])
{
try
{
RowSet cr=new OracleCachedRowSet();
cr.setUrl("jdbc:oracle:oci8:@orcl");
cr.setUsername("scott");
cr.setPassword("tiger");
cr.setCommand("delete from student");
cr.execute();
System.out.println("Command executed");
while(cr.next())
{
System.out.println("Connected and executed");
System.out.println(cr.getInt(1)+" "+cr.getString(2)+" "+cr.getString(3));
}
cr.close();
}
catch(Exception e)
{
System.out.println(e);
}
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}
}
EX2: Inserting a Record.
import java.sql.*;
import javax.sql.*;
import oracle.jdbc.rowset.*;
public class Jdbcex6
{
public static void main(String args[])
{
try
{
RowSet cr=new OracleCachedRowSet();
cr.setUrl("jdbc:oracle:oci8:@orcl");
cr.setUsername("scott");
cr.setPassword("tiger");
cr.setCommand("insert into stu values(10,’Siva’,’hyd’);
cr.execute();
System.out.println("Command executed");
while(cr.next())
{
System.out.println("Connected and executed");
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System.out.println(cr.getInt(1)+" "+cr.getString(2)+" "+cr.getString(3));
}
cr.close();
}
catch(Exception e)
{
System.out.println(e);
}
}
}
After executing above program I got the following exception.
java.lang.OutOfMemoryError:
This message means that for some reason the garbage collector is taking an excessive amount of
time (by default 98% of all CPU time of the process) and recovers very little memory in each run
(by default 2% of the heap).
This effectively means that your program stops doing any progress and is busy running only the
garbage collection at all time.
To prevent your application from soaking up CPU time without getting anything done, the JVM
throws thisError so that you have a chance of diagnosing the problem.
P) Write a Java program which illustrates the concept of JdbcRowSets.
import java.sql.*;
import javax.sql.*;
import oracle.jdbc.rowset.*;
128
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public class jdbcrow
{
public static void main(String args[])
{
try
{
JdbcRowSet cr=new OracleJdbcRowSet();
cr.setUrl("jdbc:oracle:thin:@localhost:1521:orcl");
cr.setUsername("scott");
cr.setPassword("tiger");
cr.setCommand("select * from emp student");
cr.execute();
while(cr.next())
{
System.out.println(cr.getInt(1)+" "+cr.getString(2)+" "+cr.getString(3));
}
}
catch(Exception e)
{
System.err.println(e);
}
}
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}
P) Implement the following Database operations through the front end applications by
using Swings.
Studentinfo

-
Enter Student no
Enter Name
Enter Student Address
Save
Delete
Sno
10
Update
Select
Sname
Sathya
Exit
Address
Hyderabad
import javax.swing.*;
import java.sql.*;
import java.awt.*;
import java.awt.event.*;
class first extends Frame implements ActionListener
{
130
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Connection con;
PreparedStatement ps1,ps2,ps3,ps4;
ResultSet rs;
JLabel l1,l2,l3;
JTextField tf1,tf2,tf3;
JButton b1,b2,b3,b4,b5;
first()
{
setTitle("Student info");
setSize(250,250);
FlowLayout fl=new FlowLayout();
setLayout(fl);
setBackground(Color.pink);
l1=new JLabel("Enter Student Number");
l2=new JLabel("Enter Student Name");
l3=new JLabel("Enter Student Address");
tf1=new JTextField(20);
tf2=new JTextField(20);
tf3=new JTextField(20);
b1=new JButton("INSERT");
b2=new JButton("SELECT");
b3=new JButton("DELETE");
b4=new JButton("UPDATE");
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b5=new JButton("EXIT");
add(l1);
add(tf1);
add(l2);
add(tf2);
add(l3);
add(tf3);
add(b1);
add(b2);
add(b3);
add(b4);
add(b5);
b1.addActionListener(this);
b2.addActionListener(this);
b3.addActionListener(this);
b4.addActionListener(this);
b5.addActionListener(this);
setVisible(true);
}
void dbConnect()
{
try
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{
Class.forName("oracle.jdbc.driver.OracleDriver");
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
String q1,q2,q3,q4;
q1="insert into student11 values(?,?,?)";
q2="select * from student11 where no=?";
q3="delete from student11 where no=?";
q4="update student11 set name=?,addr=? where no=?";
ps1=con.prepareStatement(q1);
ps2=con.prepareStatement(q2);
ps3=con.prepareStatement(q3);
ps4=con.prepareStatement(q4);
}
catch(Exception e)
{
e.printStackTrace();
}
}
public void actionPerformed(ActionEvent ae)
{
try
{
if(ae.getSource()==b1)
133
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{
int no;
String name,addr;
no=Integer.parseInt(tf1.getText());
name=tf2.getText();
addr=tf3.getText();
ps1.setInt(1,no);
ps1.setString(2,name);
ps1.setString(3,addr);
int i=ps1.executeUpdate();
}
if(ae.getSource()==b2)
{
int no;
String name,addr;
no=Integer.parseInt(tf1.getText());
name=tf2.getText();
addr=tf3.getText();
ps2.setInt(1,no);
rs=ps2.executeQuery();
if(rs.next())
{
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tf2.setText(rs.getString("name"));
tf3.setText(rs.getString("addr"));
}
}
if(ae.getSource()==b3)
{
int no;
no=Integer.parseInt(tf1.getText());
ps3.setInt(1,no);
int i=ps3.executeUpdate();
}
if(ae.getSource()==b4)
{
int no;
String name,addr;
no=Integer.parseInt(tf1.getText());
name=tf2.getText();
addr=tf3.getText();
ps4.setString(1,name);
ps4.setString(2,addr);
ps4.setInt(3,no);
int i=ps4.executeUpdate();
}
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if(ae.getSource()==b5)
{
dispose();
}
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
class Jdbcex6
{
public static void main(String args[])
{
first f=new first();
f.dbConnect();
}
}
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P) Develop the following GUI application which works as a SQL editor for executing every
query.
SQL Editor

Enter Query
Dno Dname
Addr
10
Sales
Hyd
20
Acc
Ban
30
HR
Chn
Result Query
Execute
Exit
import javax.swing.*;
import java.sql.*;
import java.awt.*;
import java.awt.event.*;
137
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class first extends Frame implements ActionListener
{
Connection con;
Statement st;
ResultSet rs;
JLabel l1,l2;
JTextField tf1;
JTextArea ta1;
JButton b1,b2;
String no;
String name;
String marks;
String name1;
first()
{
setTitle("Student info");
setSize(500,500);
FlowLayout fl=new FlowLayout();
setLayout(fl);
setBackground(Color.pink);
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l1=new JLabel("Enter query");
l2=new JLabel("Result");
tf1=new JTextField(20);
ta1=new JTextArea(20,20);
b1=new JButton("Execute");
b2=new JButton("Exit");
add(l1);
add(tf1);
add(l2);
add(ta1);
add(b1);
add(b2);
b1.addActionListener(this);
b2.addActionListener(this);
setVisible(true);
}
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void dbConnect()
{
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
st=con.createStatement();
}
catch(Exception e)
{
e.printStackTrace();
}
}
public void actionPerformed(ActionEvent ae)
{
try
{
if(ae.getSource()==b1)
{
name1=tf1.getText();
rs=st.executeQuery(name1);
140
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if(rs.next())
{
String empno1=rs.getString(1);
String ename1=rs.getString(2);
ta1.append(empno1);
ta1.append(ename1);
while(rs.next())
{
String empno=rs.getString(1);
String ename=rs.getString(2);
ta1.append(empno);
ta1.append(ename);
}
}
else
{
String str1="no record foud";
ta1.append(str1);
}
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}
}
catch(SQLException se1)
{
ta1.append("");
}
catch(Exception e)
{
e.printStackTrace();
}
try
{
if(ae.getSource()==b2)
{
dispose();
}
}
catch(Exception e)
{
e.printStackTrace();
}
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try
{
if(ae.getSource()==b1)
{
name1=tf1.getText();
int res=st.executeUpdate(name1);
int k=name1.indexOf('s');
if(k==2)
{
if(res>0)
{
String res1=String.valueOf(res);
ta1.append(res1+"row inserted");
}
}
int z=name1.indexOf('d');
if(z==0)
{
if(res>0)
143
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{
String res1=String.valueOf(res);
ta1.append(res1+"row deleted");
}
}
int m=name1.indexOf('d');
if(m==2)
{
if(res>0)
{
String res1=String.valueOf(res);
ta1.append(res1+"rows updated");
}
}
}
}
catch(SQLException se)
{
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ta1.append("Please correct sql query");
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
class jdbc92
{
public static void main(String args[])
{
first f=new first();
f.dbConnect();
}
}
/*OUTPUT
145
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Dealing with Dates: Dealing with Dates in JDBC is nothing but how to store string dates of Java
into Database int the form of Date Datatype of Database. The reverse process makes us to
understand getting the Database Dates into String date.
There are two proceures String dates of Java into Database in the form of Date type of
Database.
Procedure1:
1. Decide the format of the Date
EX: yyyy-mm-dd.
2. Accept the String date value depends on the format decided in step-1
String s1=”2012-05-20”
Convert String date of Java into java.sql.Datatype because java.sql.Date because
java.sql.Date is compatable with Date datatype of Database. The following method will be
use for converting String date of Java into java.sql.Date
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Java.sql.Date
Public String java.sql.DateValueOf(String)
Here String parameter represents String date
EX: java.sql.DateSd= java.sql.Date.valueOf(s1);
ps.setSting(1,”yyyy-mm-dd”);
ps.setDate(2,sql);
Note: java.sql.Date is the sub class of java.util.Date
Procedure2:
1. Decide the format and decide the value.
EX: fmt=”DD-mm-yyyy”
In order to convert String date into Date datatype of Database we must use the help of
following class
Java.text.SimpleDateFormat
SimpleDateFormat(Sting fmt)
Public java.util.Dateparse(String int value)
EX: SimpleDateFormat sdf=new SimpleDateFormat(“DD-mm-yyyy”);
Java.util.Date ud=sdf.parse(s2);
2. Convert java.util.Date int java.sql.Date by using the following API.
EX: java.util.Date
Public long getTime();
Java.sql.Date
Java.sql.Date(long)
EX: java.sql.Date sd=new java.sql.Date(ud.getTime());
ps.setString(1,”DD-mm-yyyy”);
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int i=ps.executeUpdate();
After the above steps are completed a table in the Database contains as following datatype.
FMT Name
Yyyy-mm-Dd
DD-MM-YYYY
FMT Value
20-May-2012
20-May-2012
Procedure3(Reverse process): This procedure makes us to understand how to convert date
type of Database into String date.
Procedure3: Whenever we retrieve directly the date prompt original Database it points in
standard format of Operating System(DD-mm-yyyy). But a Java programmer is interested in
printing the dates of Database in their own desired format(dd-mmm-yyyy) e.t.c.,
In order to get in our own desited format we need to go for following steps.
1. Obtain the form of Database table
EX: ResultSet rs=st.executeQuery(select * from student);
While(rs.next())
{
String fname=rs.getString(1);
}
In the above code we are retrieving the dates from Database but it comes in the format of
windows understanding format that is DD-mm-yyyy but the client is interested in retrieving
the dates of Database in String format according to the choice of the user DD-mm-yyyy,
yyyy-mmm-DD.
2. Retrieve the dates of the Database in java.sql.Date format.
EX: ResultSet rs=st.executeQuery(“select * from Date_Text”)
While(rs.next())
{
String fname=rs.get(1);
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java.sql.fmtname(1)
java.sql.DateSet=rs.getDate(2);
}
3. Create an Object simple date format class by specifying user interested format
EX: java.sql.SimpeDateFormat
1) Public SimpleDateFormat(String fmtName)
2) Public String format(java.util.Date)
EX: simpleDateFormat=new SimpleDateFormat(dd-MM-yyyy)
Format Database dates which are available in the form of java.sql.Date into String format
String fmtValue=set.format(sd);
(or)
Java.util.Date =(java.util.Date) //Object Type casting.
Before writing the program we must ensute Date_Test1 table must be created.
EX: create table date_test1(date1 date,date2 date);
String Date
Java.util.Date
Java.sql.Date
Date of
Datebase
P) Write a JDBC application which deals with accepting the Dates in String in varieties of
formats and store them in the Database in the form of Date Datatype of Database, String
format in Java.
//Inserting Date
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
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import java.util.Scanner;
public class DateTest
{
public static void main(String[] args)
{
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
//String qry="insert into date_test1 values(to_date('13-12-11','yy/dd/mm'),to_date('2013-12SEP','yyyy/dd/mm'))";
String qry="insert into date_test1 values(to_date(?,'yy/dd/mm'),to_date(?,'yyyy/dd/mm'))";
// String qry="insert into date_test values('is','is')";
PreparedStatement ps=con.prepareStatement(qry);
ps.setString(1,"12-11-10");
ps.setString(2,"2013-12-SEP");
int res=ps.executeUpdate();
//set values for positional parameters
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if(res>0)
{
System.out.println(res+"row inserted");
}
else
{
System.out.println("Record not inserted");
}
} catch (Exception e)
{
e.printStackTrace();
}
}
}
/*
create table date_test1(date1 date,date2 date);
*/
For Complete Program
Plase refer JDBC\NetBeans7.1projects\DateTest\src\InsertDateProgram.java
151
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P) Write a JDBC application which deals with retrieving the Dates in String in varieties of
formats?
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.text.SimpleDateFormat;
public class DateTest1
{
public static void main(String[] args)
{
/* Connection con=null;
Statement st=null;
ResultSet rs=null;
ResultSet rs1=null;*/
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
152
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Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from Date_test1");
while(rs.next())
{
String fname=rs.getString(1);
String fvalue=rs.getString(2);
System.out.println(fname+" "+fvalue);
}
ResultSet rs1=st.executeQuery("select * from Date_test1");
while(rs1.next())
{
String fname=rs1.getString(1);
java.sql.Date fdate=rs1.getDate(2);
java.util.Date utildate=(java.util.Date)fdate; //Object type casting
SimpleDateFormat sd=new SimpleDateFormat("yyyy-MMM-dd");
String formattedValue=sd.format(utildate);
System.out.println(fname+" "+formattedValue);
}
}
catch (Exception e)
{
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e.printStackTrace();
}
}
}
/*OUTPUT
1999-09-12 00:00:00.0 1988-10-13 00:00:00.0
2013-11-12 00:00:00.0 2013-09-12 00:00:00.0
2012-10-11 00:00:00.0 2013-09-12 00:00:00.0
2012-10-11 00:00:00.0 2013-09-12 00:00:00.0
1999-09-12 00:00:00.0 1988-Oct-13
2013-11-12 00:00:00.0 2013-Sep-12
2012-10-11 00:00:00.0 2013-Sep-12
2012-10-11 00:00:00.0 2013-Sep-12
*/
For complete program
please refer JDBC\NetBeans7.1 projects\DateTest\src\RetrieveDateProgram.java
Dealing with LOBs: So far whatever the Database applications we written they are all dealing
with numerical columns, Character columns, String columns and Data columns. In some of the
circumstances to store Large objects into the Database and we may also retrieve large objects
from the Database in order to store or retrieve large objects form the Database must support large
object and at the same time we require driver support also. For example Oracle Database
supports to deal with large objects. These are classified into two types they are
i.
ii.
i.
Character Large Objects
Binary Large Objects.
Character Large Objects: Character Large Objects deals with bulk amount of
textual messages without images.
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EX: .docfiles, .txt files, .rtf files which ever Database supports Character large objects, those
Databases must contain a predefined Datatype called CLOB.
ii.
Binary Large Objects: Binary large objects deals with images with animation,
without animation.
EX: .jpg, .img, .jped, .avi, .mov e.t.c.,
In order to deal with binary large objects we must contain a predefined Datatype called
BLOD.
EX: Create a table student with sno, sname, sphoto
Create table student(sno number, sname varchar2(10), sphoto blob)
Steps or guidelines for inserting or storing BLOBS or CLOBS:
i.
Locate name of the file which may be CLOB file or BLOB file by using an Object of
java.io.File class.
File(String)
Here String parameter represents name of CLOB or BLOB file.
EX: File f=new File(“waterlillis.jpeg”)
File f1=new File(“resume.doc”)
ii.
Open the located file in step-1 in read mode by making use of FileInputStream class.
EX: FileInputStream fs=new FileInputStream(f);
iii.
Set the values for BLOB or CLOB values for Database by using the following
methods which are present in PreparedStatement.
Java.sql.PreparedStatement
Public void setBLOB(FileInputStream, int)
Public void setCharacterStream(int, FileInputStream, int)
Public void setCharacterStream(int, FileInputStream, int)
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Here first int parameter represents column number of BLOB or CLOB in the Database.
FileInputStream class object represents name of the BLOB which is opened in read mode.
Thied int parameter represents size of the BLOB fiel or CLOB file.
EX: ps.setBLOB(3,fis, (int) f.length());
ps.setBinaryStream(3,fis,(int) f.length())
execute the query which contains interesting BLOB or CLOB file.
iv.
Int i=ps.executeUpdate();
System.err.println(i+”row inserted”);
Steps for retrieving the image from the Database:
1. Choose file name and mode and open it into write mode to the help of class for
FileOutputStream class for transferring the image from Database to main memory of the
computer.
EX: FileOutputStream fos=new FileOutpurStream(“sathya.jpeg”)
2. Get the column value of Database which belongs to BLOB type. To obtain the BLOB
type of Database column we use the following methods.
EX: java.sql.ResultSet
Public InputStream getBinaryStream(int)
(or)
Public InputStream BLOB(int)
Represents column no of Database.
EX: InputStream is=rs.getBinaryStream(s);
Here object is pointing to the image which is stored in the Database.
3. Create a Buffer for transferring image in the form of byte by byte from Database to main
memory. Single byte by byte Date transmition is taken palce, it is return recommended to
take an array of byte Datatype.
EX: Byte Buffer =new Buffer[2096]
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(The default size of the buffer is 1024 byte, 2048, 4096 e.t.c.,) that is it will be increased with the
multiples of 2.
4. Read the pixels of the image(bye by byre) from Database to main memory until end of
the file is taken place.
EX: while(byteread=is.read(buffer)!==-1)
{
Fos.write(buffer, 0 byte read)
In the above code public int read(byte[]) it is one of the predefined method present in
InputStream class and while functionality is it reads the total size of the image and placed in
byte array and it reads pixel of the Database image until end of the file is taken palce(end of
the file is indicated by -1)
Public void write(byte[])
It is one of the predefined method present in FileOutputStream class and this method is used
for writing individual values pixels if the Database image into the output file by fiel
specifying buffer size, starting position to write and what type of pixel value we are writing.
P) Write a Java application for illustrating the concept of an image into the Database and
retrieving the Database.
InsertingImage.java:
import java.io.File;
import java.io.FileInputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
public class InsertingImage
{
public static void main(String[] args) {
157
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try
{
//step-1
File f=new File("C:\\Bluehills.jpg");
//step-2
FileInputStream fis=new FileInputStream(f);
Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
String qry="insert into studentblob values(?,?,?)";
PreparedStatement ps=con.prepareStatement(qry);
ps.setInt(1,10);
ps.setString(2,"Bhargav");
ps.setBinaryStream(3,fis,(int)f.length());
int i=ps.executeUpdate();
if(i>0)
{
System.out.println(i+"row inserted");
}
else
{
System.out.println("Problem in inserting row");
}
}
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catch (Exception e)
{
e.printStackTrace();
}
}
}
/*
SQL> create table studentblob(stno number(10),sname varchar2(10),sphoto blob);
*/
For complete program
please refer JDBC\NetBeans7.1 projects\DateTest\src\InsertingImage.java
RetrievingImage.java
import java.io.FileOutputStream;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class RetrievingImage
{
public static void main(String[] args) {
try
{
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Class.forName("oracle.jdbc.driver.OracleDriver");
Connection
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
FileOutputStream fos=new FileOutputStream("C:/hills.jpg");
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from studentblob");
InputStream is=null;
if(rs.next())
{
is=rs.getBinaryStream(3);
}
byte buffer[]=new byte[4096];
int bytesread=0;
while((bytesread=is.read(buffer))!=-1)
{
fos.write(buffer,0,bytesread);
}
System.out.println("Image retrieved verify hills.jpg");
}
catch (Exception e) {
}
}
}
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For Complete program
please refer JDBC\NetBeans7.1 projects\DateTest\src\InsertingImage.java
NOTE: The same procedure even applicable for storing and retrieving character large objects
provided the following changes must be taken place in the above programs. In image insert java
we write rs or ps.setCharacterStream (-,-,-) instead of ps.setBinaryStream(-,-,-) in img, ret.java
we write following statement
rs.getCharacterStream(-)
instead of rs.getBinaryStream
Recommondations: Industry not recommended to store the image in t he Database and to
retrieve the images from Database because storing and retrieving into Database is time
consuming process to eliminate this process industry is highly recommended to store the images
in the server memory and store image location path into the Database. In JDBC programming
Type-1 drivers may not be effectively supporting to deal with LOBS. Type-2, Type-3, Type-4
are the specialized by Database and server vendors are effectively dealing with Large objects
both for retrieval and storing provided the Database software must contain BLOBs and CLOB as
a Datatype.
Q) What is the execution Status of execute() in the case of successful and unsuccessful
execution of DDL and DML statements.
A) Whenwe execute successfully with execute() then it returns false. Ohterwise true(un
successful execution) if we execute DML statements successfully with execute() then it returns
true otherwise false.
Connection Pooling: Connection pooling is one of the predefined service available in the
standalone applications of JBC and in server software. The connection pooling which is available
in Standalone JDBC applications is programmable. Whereas the Connection pooling service
available in server software is configurable. The Connection pooling concept can be utilize in
standalone JDBC applications in the form of JDBC frivers.
Connection Pooling def: A connectionPool is a factory method which contains readily available
connection objects Connection Pooling concept available in two types they are
1. Programmable managed Connection pool
2. Predefined Connection pool
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1. Programmable managed Connection pool: Connection pools are those which are
created by JDBC programmer that is connections are created by programmers and
managed by programmers and releasing or destructing the connection also done by
programmer this type of process is not recommended. But recommended to use
predefined connection pooling concept.
2. Predefined Connection pool: Predefined Connection pools are those which are either
managed by JDBC drivers or managed by server softwares. That is connections creation,
managing the connections and destroying the connections will be done by either JDBC
drivers or Server softwares.
API: The concept of Connection pooling available in JDBC in the form of two interfaces
present in javax.sql.* package they are
1. Java.sql.ConnectionPoolDataSource
2. Javax.sql.PooledConnection
The above interfaces are implemented by various Database vendors like IBM, Oracle
e.t.c., for example Oracle Corporation has developed the following class for providing
Connection pooling concept.
OralceConnectionPoolDataSoruce. This is the predefined class present in
Oracle,jdbc.pool.*. It is oen of the subclass of javax.sql.Datasource hence creating a
connection pool is nothing but creating an object of OracleConnectionPoolDataSource.
EX: OracleConnectionPoolDataSource ocp=new OracleConnectionPoolDataSource()
Each and every Connection Pool is associated with a unique name called Datasource which is
nothing but an object of OracleConnectionPoolDataSource.
Steps for implementing JDBC application with ConnectionPooling Concept:
1. Create a Connection pool and make it to associated with a distinct DataSource name.
2. Specify the Connection parameters for creating for creating number of records available
connection pool. To specify the connection parameters we use the following methods
i.
Public void setDriverType(String)  Thin or oci8
ii.
Public void setServiceName(String)  localhost
iii.
Public void setProtNumber(int)  Protno
iv.
Public void setUser(String)  UserName
v.
Public void setPassword(String)  Password
Steps:
1. Java programmer develops a JDBC application
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2.
3.
4.
5.
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6.
As a part of JDBC application programmer creates Connection pool.
JDBC application request the connection pool to grant a connection Object.
Connection Pool gives a Connection object to the JDBC application.
JDBC application receives a Connection object from Connection pool(An object of
pooled connection interface)
Every JDBC application obtains physical Connection JDBC application and Database
software by using an object of Pooled Connection interface that is an object
PooledConenction interface(That is an Object of java.sql.ConnectionInterface)
Database software extends the queries/ performs the Database operations depends on type
of queries passed form JDBC applications.
Database software gives the result back to the JDBC application depends on type of
query executed.
JDBC application receives the result form Database software and display on the console.
7.
8.
9.
P) Write a Java Program which illustrate the concept of JDBC Connection Pooling.
import java.sql.*;
import javax.sql.*;
import oracle.jdbc.pool.*;
class jdbcpool
{
public static void main(String args[])throws Exception
{
//step-1
OracleConnectionPoolDataSource ds=new OracleConnectionPoolDataSource();
//step-2
ds.setDriverType("thin");
ds.setServerName("localhost");
ds.setPortNumber(1521);
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ds.setServiceName("orcl");
ds.setUser("scott");
ds.setPassword("tiger");
//step-3
PooledConnection pcon=ds.getPooledConnection();
System.out.println("borrowed one Connection object from Connection pool");
//step-4
Connection con=pcon.getConnection();
System.out.println("Obtaining the connection from oracle");
//step-5
Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select * from dept");
while(rs.next())
{
System.out.println(rs.getString(1)+" "+rs.getString(2));
}
rs.close();
st.close();
con.close();
}
}
Savepoint in JDBC(4.0): In the ordinary batch process either we are executing all the
transactions or not executing any transactions at all that is either all the transactions are
commiting or no transactions are commiting this indicates no controlling mechanism about the
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transactions in order to provide transaction controlling mechanism we need to use the concept of
Savepoing.
DEF: A Savepoint is the breaking point with in the transactions to decide which transactions are
supposed to committed and which transaction as are rollbacked. What are all transactions used
before the Savepoint creation, those transaction results will be committed what are all the
transactions we use after the savepoint creation their results be rollbacked.
API: To deal with the concept of Savepoint we use predefined interface called
java.sql.Savepoint.
To create a Savepoint we use following method
Java.sql.Connection
Public Savepoint setSavepoint(String)
Here the parameter String represents name of the Savepoint.
EX: Savepoint sp=con.setSavepoint(“spt”);
Let us consider the following code snippet.
con.setAutoCommit(false)
T1 DML Statement
T2 DML Statement
T3 DML Statement
Savepoint sp=new Savepoint(‘so’);
T4DML Statement
T5 DML Statement
In the above example the transactions results T1,T2,T3 are committed and the transactions
results T4 and T5 will be rollback provided we must call Rollback() with respect Connection
interface object by passing the reference of Savepoint.
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P) Write a JDBC application which illustrates the concept of Savepoint.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Savepoint;
import java.sql.Statement;
public class SavePoint1
{
static Connection con=null;
static Statement st=null;
public static void main(String[] args) {
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
con=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","scott","tiger");
con.setAutoCommit(false);
st=con.createStatement();
int i=st.executeUpdate("insert into dept1 values(23,'SE','TPT')");
System.out.println(i+"row inserted");
Savepoint sp=con.setSavepoint("spt");
int j=st.executeUpdate("update dept1 set dname='EDU' where deptno=11");
int k=st.executeUpdate("delete from dept1 where deptno=12");
System.out.println(k+"row deleted");
con.rollback(sp);
con.setAutoCommit(true);
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con.commit();
} catch (Exception e)
{
System.err.println("Problem in Database");
}
}
}
/*After executing this program just observe in Database there is one row inserted and no row
deleted and updated.
Table is
create table dept1(deptno number(5),dname varchar2(10),loc varchar2(10));
Before Running the program
DEPTNO DNAME
LOC
------- ---------- ---------10 SALES
PLVD
11 HR
KDP
12 FIN
JMD
10 ACC
KNL
After Running the Program
DEPTNO DNAME
LOC
-------- ---------- ---------10 SALES
11 HR
PLVD
KDP
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12 FIN
10 ACC
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JMD
KNL
TPT
*/
For complete program
please refer JDBC\NetBeans7.1 projects\DateTest\src\SavePoint1.java
s
168