E-R Model for Flower Store
Products m
1
Used for n
Occasion m
Orderline m 1
Orders m m
1
Recipient
Customer
1
SQL - 1

Data Definition and
Manipulation with SQL
SQL - 2

Structured Query Language
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Developed by IBM
A standard for relational database access
IBM DB2, Microsoft SQL server, Oracle,
MySQL (open source)
SQL - 3

Data Definition Language
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A data definition language (DDL) is used to define a database in DBMS.
A schema is a specification (or definition) of a database using the DDL.
Create table
Create view
Create index
Integrity control
SQL - 4

Table Definition with SQL
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CREATE TABLE ORDERS
(ORDER# INTEGER NOT NULL,
CUSTOMER_ID CHAR(4),
ORDER_DATE
AMOUNT
DATE,
DECIMAL (8,2))
IN DATABASE INVENTORY
ALTER TABLE ORDERS
ADD DISCOUNT SMALLINT
DROP TABLE ORDERS
CREATE SYNONYM CUSTORDER FOR
ORDERS
SQL - 5

View Definition with SQL
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CREATE VIEW GOODSTUD
(NAME, COURSE)
AS SELECT SNAME, CNAME
FROM STUD, ENROLL
WHERE STUD.SID = ENROLL.ID
AND ENROLL.GRADE = ‘A’
View can be used for data retrieval as virtual table
Not all views are updateable (insert, delete, update)
SQL - 6

Index Definition with SQL
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Index is used to provide rapid random and sequential access
Consume extra storage space and maintenance time
Data access does not depend on the existence of index
SQL - 7

Create Index
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CREATE INDEX DES ON
PRODUCTS (DESCRIPTION)
IN DATABASE INVENTORY
CREATE UNIQUE INDEX XP
ON PRODUCTS(PRODUCT#)
CREATE UNIQUE INDEX SXP
ON SUPPLY (SUPPLYER#, PRODUCT#)
DROP INDEX XP
SQL - 8

Data Integrity Control
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Integrity refers to the accuracy or validity of data.
(validity check)
Key restrictions

 not null must be unique
Domain restrictions
 format
 range
Cross reference restrictions (referential integrity)
 valid foreign keys
SQL - 9

Integrity Control with SQL

Entity Integrity
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No part of the primary key can be null.
Primary key must be unique

Specify PRIMARY KEY or define a unique index over that key
SQL - 10

Integrity Control with SQL

Referential Integrity
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Insertion Integrity -- No row can be added into a dependent table unless the foreign key matches a primary key in parent table or the foreign key value is null (optional relationship)
Update Integrity -- Prevents the altering of any primary key value if there are dependent rows with matching values
(different from ON UPDATE CASCADE in the textbook)
Deletion Integrity -- Restrict, Cascade, and Set null
SQL - 11

Integrity Control with SQL

A general form:
CREATE TABLE table-name
(column-name type [NOT NULL], column-name type [NOT NULL],
...
[ PRIMARY KEY ( column-name) ]
[ FOREIGN KEY (column-name) REFERENCES table-name
ON DELETE RESTRICT | CASCADE | SET NULL
ON UPDATE CASCADE ] )
IN DATABASE database-name
EDITPROC edit-routine
VALIDPROC validation-routine
SQL - 12

Integrity Control with SQL

ON DELETE clause
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RESTRICT -- makes users unable to delete a parent row if there are matching dependent rows
CASCADE -- when a parent row is deleted, all dependent rows will be deleted
SET NULL -- when a parent row is deleted, set the foreign key value to null in all the dependent rows.
SQL - 13

Integrity Control with SQL


EDITPROC clause
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A routine that cannot contain any DB2 statements will be automatically invoked after retrieval or before storing a row. Used for data compression, decompression and encryption
VALIDPROC clause

An executable routine that will be invoked just before a row is stored. Used for data validation.
SQL - 14

Integrity Control with SQL

An example
CREATE TABLE ENROLL
(CID CHAR(4) NOT NULL,
SID CHAR(4) NOT NULL,
GRADE CHAR(2),
PRIMARY KEY ( CID,SID),
FOREIGN KEY (CID) REFERENCES COURSE
ON DELETE RESTRICT,
FOREIGN KEY (SID) REFERENCES STUDENT
ON DELETE CASCADE)
IN DATABASE your-database-name
SQL - 15

Data Dictionary / Directory
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The data dictionary contains definitions of records, data items, relations and other data objects that are of interest to users or required by data management software.
The data directory contains information about where data are stored that is used exclusively by data management software.
System catalog
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Systables
Syscolumns

Sysindex
SQL - 16

Database Design using
Microsoft Access
SQL - 17

SQL - 18

Basic Components of Access
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Table
Query
Forms
Report
Macro
Module
SQL - 19

Database Creation using
MicroSoft Access
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Create table
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Specify field data type
Specify key
Specify field properties (domain constraints)
Create relationships

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Specify relationship between tables
Specify relationship integrity control
SQL - 20

Create Tables
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Specify fields
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Field name, data type, description, and properties (input mask, default, lookup, etc.)
Specify Primary Key

Single and concatenated
Specify Table Name
SQL - 21

Set a field’s data type
Open the table in design view
Set a field’s data type
Choose a primary key
Set field properties
SQL - 22

Domain constraints
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Size
Format
Default value
Validation rules
Index
Required
Lookup
SQL - 23

Specify relationship and integrity control
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Specify links between tables
Integrity control: enforce referential integrity cascade update related fields cascade delete related records
SQL - 24

Relationships and Integrity Control
SQL - 25

Practice: Create Four tables
Using Access
SQL - 26

SQL - 27

SQL - 28

You need to enter data separately to Orders and Orderln tables SQL - 29

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Data Manipulation Language
A Data Manipulation Language (DML) is used to describe the processing of the database.
select Name, Salary from Staff where Salary > 15000 insert into Staff
(ID, Name, Dept, Salary) values (510, ‘Harrison’, 38, 15400) update Staff set Salary = Salary * 1.15
where ID = 510 delete from Staff where ID = 540
SQL - 30

Relational Data Manipulation
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Relational algebra
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Manipulates one or two relations as operands and produces a new relation as the result.
Relational calculus
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Manipulates relations implicitly by specifying conditions that can involve attributes from several relations.
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Structured Query Language (SQL)
Tabular / Graphic data manipulation
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Query - By- Example (QBE)
Most PS DBMS use variations of QBE
SQL - 31

Sample table
Q.STAFF
ID NAME DEPT JOB YEARS
10 SANDERS D20 MGR
20 PERNAL D20 SALES
30 MARENGHI D38 MGR
40 O’BRIEN D20 SALES
50 HANES
80 JAMES
7
8
5
6
D15 MGR 10
D20 CLERK -
DEPTNUMB DEPTNAME
Q.ORG
MANAGER DIVISION
SALARY COMM
18357.50 -
18171.25 612.45
17506.75 -
18006.00 846.55
20659.80 -
13540.60 -
LOCATION
D10
D15
D20
D38
HEAD OFFICE
NEW ENGLAND
160
50
MID ATLANTIC 10
SOUTH ATLANTIC 30
CORPORATE NEW YORK
EASTERN BOSTON
EASTERN
EASTERN
WASHINGTON
ATLANTA
SQL - 32

Tabular / Graphic data manipulation

Query - By- Example (QBE)
List department managers with salary > 20000
Q.STAFF | ID | DEPT | NAME | JOB | YEARS | SALARY
----------+--------+--------+--------+------+---------+-------------
| _MG | | P. | | | >20000
Q.ORG | DEPTNUMB | MANAGE | DIVISION | LOATION
----------+---------------+-----------+-------------+--------------
| P. AO. | _MG | |

Now widely used by PC RDBMS with many variations
SQL - 33

QBE Query in Access
SQL - 34

Relational Algebra select project join
SQL - 35

Relational Algebra
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SELECT -- Extract specified tuples from a relation.
PROJECT -- Extract specified attributes from a relation.
JOIN -- Combines data from two relations based on values for a common attribute
SQL - 36

Types of Join (pp.225-227)
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Student JOIN Enrollment on
Student.StudentID = Enrollment.StudentNumber
Equi join
Natural Join (not duplicate join fields)
Inner Join (not allow null in join fields)
Outer Join (allow null in join fields)

Left outer join (include all records in left join table
Student)

Right outer join (include all records in right join table
Enrollment
SQL - 37

Relational Calculus -- SQL

General form for data retrieval in SQL:
SELECT [ DISTINCT ] field(s)
FROM table(s)
[ WHERE predicate]
[ GROUP BY field(s) [ HAVING predicate ] ]
[ ORDER BY field(s)]
SQL - 38

Predicate

Operations:
Arithmetic operators:
+ - * /
Comparison operators:
= > >= <=
Boolean operators:
AND OR NOT IN BETWEEN LIKE
SQL - 39

Sample table
STAFF
ID NAME DEPT JOB YEARS
10 SANDERS D20 MGR
20 PERNAL D20 SALES
30 MARENGHI D38 MGR
40 O’BRIEN D20 SALES
50 HANES
80 JAMES
7
8
5
6
D15 MGR 10
D20 CLERK -
DEPTNUMB DEPTNAME
ORG
MANAGER DIVISION
SALARY COMM
18357.50 -
18171.25 612.45
17506.75 -
18006.00 846.55
20659.80 -
13540.60 -
LOCATION
D10
D15
D20
D38
HEAD OFFICE
NEW ENGLAND
160
50
MID ATLANTIC 10
SOUTH ATLANTIC 30
CORPORATE NEW YORK
EASTERN BOSTON
EASTERN
EASTERN
WASHINGTON
ATLANTA
SQL - 40

Simple SQL Queries
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SELECT *
FROM STAFF
SELECT DISTINCT DEPT, JOB
FROM STAFF
ID NAME
Q.STAFF
DEPT JOB YEARS
10 SANDERS D20 MGR
20 PERNAL D20 SALES
7
8
30 MARENGHI D38 MGR
40 O’BRIEN D20 SALES
5
6
50 HANES
80 JAMES
D15 MGR 10
D20 CLERK -
SALARY COMM
18357.50 -
18171.25 612.45
17506.75 -
18006.00 846.55
20659.80 -
13540.60 -
SQL - 41

Simple SQL Queries
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SELECT DEPT, NAME
FROM STAFF
ORDER BY DEPT DESC, NAME
SELECT ID, SALARY+COMM
FROM STAFF
WHERE DEPT = ‘D20’
ID NAME
10 SANDERS
20 PERNAL
DEPT JOB
D20
D20
MGR
SALES
30 MARENGHI D38
40 O’BRIEN D20
50 HANES D15
80 JAMES D20
MGR
SALES
MGR
CLERK
YEARS
7
8
5
6
10
-
SALARY COMM
18357.50 -
18171.25 612.45
17506.75 -
18006.00 846.55
20659.80 -
13540.60 -
SQL - 42

Conditions
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WHERE SALARY / 12 < COMM * 4
WHERE COMM BETWEEN 200 AND 300
WHERE DEPT IN (‘D20’,’D38’,’D40’)
WHERE JOB =‘SALES’ AND (SALARY>18000
OR COMM >500)
WHERE NAME LIKE ‘W%’
WHERE ADDRESS LIKE ’%NY’
WHERE NOT JOB =‘MGR’
WHERE YEARS NOT NULL
SQL - 43

Built-in Functions
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Functions: COUNT SUM AVG MIN MAX
Find out clerk’s average and minimum salary for each department
SELECT DEPT,
AVG (SALARY), MIN (SALARY), COUNT (*)
FROM STAFF
WHERE JOB =‘CLERK’
GROUP BY DEPT
SQL - 44

More Queries

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How many different jobs?
SELECT COUNT (DISTINCT JOB)
FROM STAFF
Who ‘s salary is above average?
SELECT NAME, SALARY
FROM STAFF
WHERE SALARY > ( SELECT
AVG(SALARY) FROM STAFF )
SQL - 45

Group By and Having
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HAVING is always followed by a built-in function
HAVING must follow GROUP BY
HAVING conditions only apply to grouped data
SQL - 46

Group By and Having
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
Find out average salary for each department with more than 4 employees
SELECT DEPT, AVG(SALARY)
FROM STAFF
GROUP BY DEPT
HAVING COUNT(*) > 4
Find out department with average salary higher than company’s average
SELECT DEPT, AVG(SALARY)
FROM STAFF
GROUP BY DEPT
HAVING AVG( SALARY) > (SELECT AVG(SALARY)
FROM STAFF)
SQL - 47

Join


List manager’s name for each division and each department
SELECT DIVISION, DEPTNAME, NAME
FROM ORG, STAFF
WHERE STAFF.DEPT = ORG.DEPTNUMB
AND JOB = ‘MGR’
ORDER BY DIVISION, DEPTNAME
Must specify the join condition based on the equal value of two common attributes from two tables. You can join more than two tables at the same time
SQL - 48

Join specified in MicroSoft SQL and Access SQL


List manager’s name for each division and each department
SELECT DIVISION, DEPTNAME, NAME
FROM ORG INNER JOIN STAFF
ON STAFF.DEPT = ORG.DEPTNUMB
WHERE JOB = ‘MGR’
ORDER BY DIVISION, DEPTNAME
In Microsoft SQL, INNER JOIN is specified in
FROM clause
SQL - 49

Correlation Variables

List employees whose salary is greater than their manager’s salary
SELECT X.NAME, Y.SALARY
FROM STAFF X, STAFF Y,
WHERE X.DEPT =Y.DEPT
AND Y.JOB = ‘MGR’
AND X.SALARY >Y.SALARY

X, Y are correlation variables refer to STAFF twice
SQL - 50

Find out Unknown Condition
Values: ANY, ALL, EXIST

List employees who work in
EASTERN division
SELECT NAME, ID
FROM STAFF
WHERE DEPT = ANY
(SELECT DEPTNUMB FROM ORG WHERE
DIVISION = ‘EASTERN’)
SQL - 51


Find the department with highest average salary
SELECT DEPT, AVG(SALARY) FROM STAFF
GROUP BY DEPT
HAVING AVG(SALARY) >= ALL
(SELECT AVG(SALARY) FROM STAFF GROUP
BY DEPT)
SQL - 52


List all managers who are not the department managers
SELECT ID, NAME, DEPT FROM STAFF XYZ
WHERE JOB =‘MGR’ AND NOT EXIST
(SELECT * FROM ORG WHERE MANAGER =
XYZ.ID)
SQL - 53

Union - Merging two or more resulting tables


Union is different from join list all employees with less than 3 year employment and applicants with more than
14 year education
SELECT NAME ‘EMPLOYEE’ FROM STAFF WHERE YEARS < 3
UNION
SELECT NAME, ‘APPLICANT’ FROM APPLICANT
WHERE EDLEVEL >14
NAME EXPRESSION1
BURKE EMPLOYEE
GASPARD APPLICANT
JACOBS APPLICANT
SQL - 54

Retrieve and Modify Data through a View


Create a view SALES as a list of all sales persons
CREATE VIEW SALES ( DIVISION, DEPARTMENT, NAME,
INCOME) AS
SELECT DIVISION, DEPTNAME, NAME, SALARY+COMM
FROM STAFF, ORG
WHERE DEPT = DEPTNUMB AND JOB = ‘SALES’
A view can be used in the same way as table for data retrieval
SQL - 55

Data Modification Restriction

Restrictions for data modification through a view

Only views that are simple row-and-column subset of a base table are updateable


A column in a view derived from mathematical expression on base data may not be updated
A new row may not be inserted into a view when the base table affected would have a missing value for a NOT NULL column.
SQL - 56

Practice



List all sales people’s name in the Eastern division sorted by name
List number of employees and average salary in each division
Tables:
STAFF
(ID, NAME,DEPT,JOB,YEARS,SALARY,COMM)
ORG
(DEPTNUMB,DEPTNAME,MANAGER,DIVISION
,LOCATION)
SQL - 57

Sample table
STAFF
ID NAME DEPT JOB YEARS
10 SANDERS D20 MGR
20 PERNAL D20 SALES
30 MARENGHI D38 MGR
40 O’BRIEN D20 SALES
50 HANES
80 JAMES
7
8
5
6
D15 MGR 10
D20 CLERK -
DEPTNUMB DEPTNAME
ORG
MANAGER DIVISION
SALARY COMM
18357.50 -
18171.25 612.45
17506.75 -
18006.00 846.55
20659.80 -
13540.60 -
LOCATION
D10
D15
D20
D38
HEAD OFFICE
NEW ENGLAND
160
50
MID ATLANTIC 10
SOUTH ATLANTIC 30
CORPORATE NEW YORK
EASTERN BOSTON
EASTERN
EASTERN
WASHINGTON
ATLANTA
SQL - 58

Practice Answer 1


List all sales people’s name in the
Eastern division sorted by name
SELECT NAME
FROM STAFF, ORG
WHERE DEPT = DEPTNUMB
AND JOB = ‘SALES’
AND DIVISION = ‘EASTERN’
ORDER BY NAME
SQL - 59

Practice Answer 2


List number of employees and average salary in each division
SELECT DIVISION, COUNT (*), AVG
(SALARY)
FROM STAFF, ORG
WHERE DEPT = DEPTNUMB
GROUP BY DIVISION
SQL - 60

Making Queries using Access

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
Add tables
Select fields for display
Using expression to display calculated fields
Specify criteria
Total: group by, sum, avg, count, min,max
Sort
Run, modify and save
SQL view
SQL - 61

The date format is #mm/dd/yy#
SQL - 62

Query

List total number of items sold by each product
SQL - 63

SQL - 64

SQL - 65

SQL View
SELECT Products.Product_Name,
Sum(Orderln.Quantity) AS
QuantityOfSum
FROM Products INNER JOIN Orderln ON
Products.Product_Code =
Orderln.Product_Code
GROUP BY Products.Product_Name;
SQL - 66

List Order Details

List Order Details including Order
Number, Order Date, Customer Name,
Ordered items, quantity, unit price, and extend price for each order.
SQL - 67

SQL - 68

SQL - 69

SQL View

SELECT Customers.Customer_Name,
Orders.Order_Number, Orders.Order_Date,
Orderln.Product_Code, Products.Product_Name,
Products.Unit_Price, Orderln.Quantity,
[Unit_Price]*[Quantity] AS [Extend Price]
FROM Products INNER JOIN ((Customers INNER
JOIN Orders ON Customers.Customer_Name =
Orders.Customer_Name) INNER JOIN Orderln ON
Orders.Order_Number = Orderln.Order_Number) ON
Products.Product_Code = Orderln.Product_Code
WHERE (((Orders.Order_Date)>#1/1/2002#));
SQL - 70

Online SQL Tutorial

 http://www.dbbm.fiocruz.br/class/Lectu re/d17/sql/jhoffman/sqltut.html
http://www.db.cs.ucdavis.edu/teaching/ sqltutorial/tutorial.pdf
SQL - 71

SQL - 72