PL/SQL Control Statement
By
ukmodak
|
March 31st 2024 10:32:28 AM
| viewed
562
times
IF statement:
| Sl No |
Condition |
Example |
| 1 |
IF - THEN statement |
DECLARE
a number(2) := 10;
BEGIN
a:= 10;
-- check the boolean condition using if statement
IF( a < 20 ) THEN
-- if condition is true then print the following
dbms_output.put_line('a is less than 20 ' );
END IF;
dbms_output.put_line('value of a is : ' || a);
END;
/
|
| 2 |
IF-THEN-ELSE statement |
DECLARE
a number(3) := 100;
BEGIN
-- check the boolean condition using if statement
IF( a < 20 ) THEN
-- if condition is true then print the following
dbms_output.put_line('a is less than 20 ' );
ELSE
dbms_output.put_line('a is not less than 20 ' );
END IF;
dbms_output.put_line('value of a is : ' || a);
END;
/
|
| 3 |
IF-THEN-ELSIF statement |
DECLARE
a number(3) := 100;
BEGIN
IF ( a = 10 ) THEN
dbms_output.put_line('Value of a is 10' );
ELSIF ( a = 20 ) THEN
dbms_output.put_line('Value of a is 20' );
ELSIF ( a = 30 ) THEN
dbms_output.put_line('Value of a is 30' );
ELSE
dbms_output.put_line('None of the values is matching');
END IF;
dbms_output.put_line('Exact value of a is: '|| a );
END;
/
|
| 4 |
Case statement |
DECLARE
grade char(1) := 'A';
BEGIN
CASE grade
when 'A' then dbms_output.put_line('Excellent');
when 'B' then dbms_output.put_line('Very good');
when 'C' then dbms_output.put_line('Well done');
when 'D' then dbms_output.put_line('You passed');
when 'F' then dbms_output.put_line('Better try again');
else dbms_output.put_line('No such grade');
END CASE;
END;
/
|
| 5 |
Searched CASE statement |
DECLARE
grade char(1) := 'B';
BEGIN
case
when grade = 'A' then dbms_output.put_line('Excellent');
when grade = 'B' then dbms_output.put_line('Very good');
when grade = 'C' then dbms_output.put_line('Well done');
when grade = 'D' then dbms_output.put_line('You passed');
when grade = 'F' then dbms_output.put_line('Better try again');
else dbms_output.put_line('No such grade');
end case;
END;
/
|
| 6 |
nested IF-THEN-ELSE |
DECLARE
a number(3) := 100;
b number(3) := 200;
BEGIN
-- check the boolean condition
IF( a = 100 ) THEN
-- if condition is true then check the following
IF( b = 200 ) THEN
-- if condition is true then print the following
dbms_output.put_line('Value of a is 100 and b is 200' );
END IF;
END IF;
dbms_output.put_line('Exact value of a is : ' || a );
dbms_output.put_line('Exact value of b is : ' || b );
END;
/
|
Loop Statement:
| Sl No |
Condition |
Example |
| 1 |
PL/SQL Basic LOOP |
DECLARE
x number := 10;
BEGIN
LOOP
dbms_output.put_line(x);
x := x + 10;
IF x > 50 THEN
exit;
END IF;
END LOOP;
-- after exit, control resumes here
dbms_output.put_line('After Exit x is: ' || x);
END;
/
DECLARE
x number := 10;
BEGIN
LOOP
dbms_output.put_line(x);
x := x + 10;
exit WHEN x > 50;
END LOOP;
-- after exit, control resumes here
dbms_output.put_line('After Exit x is: ' || x);
END;
/
|
| 2 |
PL/SQL WHILE LOOP |
DECLARE
a number(2) := 10;
BEGIN
WHILE a < 20 LOOP
dbms_output.put_line('value of a: ' || a);
a := a + 1;
END LOOP;
END;
/
|
| 3 |
PL/SQL FOR LOOP |
DECLARE
a number(2);
BEGIN
FOR a in 10 .. 20 LOOP
dbms_output.put_line('value of a: ' || a);
END LOOP;
END;
/
DECLARE
a number(2) ;
BEGIN
FOR a IN REVERSE 10 .. 20 LOOP
dbms_output.put_line('value of a: ' || a);
END LOOP;
END;
/
|
| 4 |
Nested loops in PL/SQL |
DECLARE
i number(3);
j number(3);
BEGIN
i := 2;
LOOP
j:= 2;
LOOP
exit WHEN ((mod(i, j) = 0) or (j = i));
j := j +1;
END LOOP;
IF (j = i ) THEN
dbms_output.put_line(i || ' is prime');
END IF;
i := i + 1;
exit WHEN i = 50;
END LOOP;
END;
/
|
| 5 |
Labeling a PL/SQL Loop |
DECLARE
i number(1);
j number(1);
BEGIN
<< outer_loop >>
FOR i IN 1..3 LOOP
<< inner_loop >>
FOR j IN 1..3 LOOP
dbms_output.put_line('i is: '|| i || ' and j is: ' || j);
END loop inner_loop;
END loop outer_loop;
END;
/
|
| 6 |
PL/SQL EXIT |
DECLARE
a number(2) := 10;
BEGIN
-- while loop execution
WHILE a < 20 LOOP
dbms_output.put_line ('value of a: ' || a);
a := a + 1;
IF a > 15 THEN
-- terminate the loop using the exit statement
EXIT;
END IF;
END LOOP;
END;
/
|
| 6 |
PL/SQL CONTINUE |
DECLARE
a number(2) := 10;
BEGIN
-- while loop execution
WHILE a < 20 LOOP
dbms_output.put_line ('value of a: ' || a);
a := a + 1;
IF a = 15 THEN
-- skip the loop using the CONTINUE statement
a := a + 1;
CONTINUE;
END IF;
END LOOP;
END;
/
|
| 7 |
PL/SQL GOTO |
DECLARE
a number(2) := 10;
BEGIN
<>
-- while loop execution
WHILE a < 20 LOOP
dbms_output.put_line ('value of a: ' || a);
a := a + 1;
IF a = 15 THEN
a := a + 1;
GOTO loopstart;
END IF;
END LOOP;
END;
/
A GOTO statement cannot branch into an IF statement, CASE statement, LOOP statement or sub-block.
A GOTO statement cannot branch from one IF statement clause to another or from one CASE statement WHEN clause to another.
A GOTO statement cannot branch from an outer block into a sub-block (i.e., an inner BEGIN-END block).
A GOTO statement cannot branch out of a subprogram. To end a subprogram early, either use the RETURN statement or have GOTO branch to a place right before the end of the subprogram.
A GOTO statement cannot branch from an exception handler back into the current BEGIN-END block. However, a GOTO statement can branch from an exception handler into an enclosing block.
|
| 7 |
PL/SQL FORALL (use on collection for update data ) |
SET SERVEROUTPUT ON;
DECLARE
--Source collection
TYPE My_NestedTable IS TABLE OF NUMBER;
source_col My_NestedTable := My_NestedTable (9,18,27,36,45,54,63,72,81,90);
--Indexing collection
TYPE My_Array IS TABLE OF PLS_INTEGER INDEX BY PLS_INTEGER;
index_col My_Array;
BEGIN
--Initializing indexing collection with the index numbers.
index_col (1) := 3;
index_col (5) := 7;
index_col (12):= 8;
index_col (28):= 10;
--FORALL statement
FORALL idx IN VALUES OF index_col
INSERT INTO tut_79 VALUES (source_col (idx));
END;
/
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