PRACTICE 3
Ms. Reham Alhaweal
rhaweal@gmail.com
1) Identify valid and invalid identifier names:
• today
• last_name
 Valid  Invalid
 Valid  Invalid
 Valid  Invalid
• today’s_date
• Number_of_days_in_February_t
 Valid  Invalid
his_year
 Valid  Invalid
• Isleap$year
• #number
 Valid  Invalid
• NUMBER#
 Valid  Invalid
• number1to7
 Valid  Invalid
1) Identify valid and invalid identifier names:
• today
• last_name
 Valid  Invalid
 Valid  Invalid
 Valid  Invalid
• today’s_date
• Number_of_days_in_February_t
 Valid  Invalid
his_year
 Valid  Invalid
• Isleap$year
• #number
 Valid  Invalid
• NUMBER#
 Valid  Invalid
• number1to7
 Valid  Invalid
2) Identify valid and invalid variable
declaration and initialization:
• printer_name constant
VARCHAR2(10);
 Valid
Invalid
• deliver_to VARCHAR2(10):=Ahmad;
 Valid
 Invalid
• by_when DATE:=
CURRENT_DATE+1;
 Valid
 Invalid
2) Identify valid and invalid variable
declaration and initialization:
• printer_name constant
VARCHAR2(10);
 Valid
Invalid
• deliver_to VARCHAR2(10):=Ahmad;
 Valid
 Invalid
• by_when DATE:=
CURRENT_DATE+1;
 Valid
 Invalid
Examine the following anonymous block and choose the
appropriate statement.
(Note: the ServerOutput already sets ON)
DECLARE
v_fname VARCHAR2(20);
v_lname VARCHAR2(15) DEFAULT 'Mohammed';
BEGIN
DBMS_OUTPUT.PUT_LINE(v_fname ||’ ‘
||v_lname);
END;
/
The block executes successfully and print “Mohammed.”
The block returns an error because the fname variable is used without
initializing.
The block executes successfully and print “null Mohammed.”
The block returns an error because you cannot use the DEFAULT
keyword to initialize a variable of type VARCHAR2.
The block returns an error because the v_fname variable is not
declared.
The block executes successfully and print “Mohammed.”
The block returns an error because the fname variable is used without
initializing.
The block executes successfully and print “null Mohammed.”
Create and execute a simple anonymous block:
1. That outputs:“Hello World.”
2. Add a declarative section to this PL/SQL block. In the
declarative section, declare the following variables:
• Variable v_today of type DATE. Initialize today with
SYSDATE.
• Variable v_tomorrow of type today. Use %TYPE
attribute to declare thisvariable.
3. In the executable section, initialize the tomorrow
variable with an expression, which calculates
tomorrow’s date (add one to the value in today). Print
the value of today and tomorrow after printing “Hello
World.” . Also print your name.
4. Execute and save this script as lab_02_04.sql
SET SERVEROUTPUT
DECLARE
v_today DATE:=SYSDATE;
v_tomorrow v_today%TYPE;
BEGIN
v_tomorrow := v_today+1;
DBMS_OUTPUT.PUT_LINE('Hello World ..'
|| CHR(10)||'Today
is:'||v_today||CHR(10)|| 'Tomorrow
will be : ' || v_tomorrow || CHR(10)
||’My name is : YOUR NAME');
END;
/
Edit the lab_02_04.sql script
1. Add code to create two bind variables.
Create bind variables b_basic_percent and
b_pf_percent of type NUMBER.
2. In the executable section of the PL/SQL block,
assign the values 45 and 12 to b_basic_percent
and b_pf_percent, respectively.
3. Terminate the PL/SQL block with “/” and
display the value of the bind variables by using
the PRINT command.
4. Execute and save your script file as
lab_02_05.sql
SET SERVEROUTPUT ON
SET AUTOPRINT ON
VARIABLE b_basic_percent NUMBER;
VARIABLE b_pf_percent NUMBER;
DECLARE
v_today DATE:=SYSDATE;
v_tomorrow v_today%TYPE;
BEGIN
v_tomorrow := v_today+1;
DBMS_OUTPUT.PUT_LINE('Hello World '||CHR(10)||
'Today is: '|| v_today || CHR(10)||'Tomorrow
will be : '||v_tomorrow||CHR(10)||
'My name is : YOU NAME');
:b_basic_percent := 45;
:b_pf_percent := 12;
END;
/
Using Product Sales database, create and execute
an anonymous block that allow user to inter a
product ID and print a product name of a it.
SET SERVEROUTPUT ON
SET VERIFY OFF
DECLARE
PRODUCTID NUMBER (10) := &PRODUCTID;
P_NAME PRODUCTS.PRODUCT_NAME%TYPE;
BEGIN
SELECT PRODUCT_NAME INTO P_NAME
FROM PRODUCTS WHERE PRODUCT_ID =
PRODUCTID;
DBMS_OUTPUT.PUT_LINE(CHR(10)
||'Product name is : ' || P_NAME);
END;
/