You may use the IF, THEN, ELSE, ELSIF, and END IF keywords in PL/SQL for performing conditional logic.
The following syntax illustrates the use of conditional logic:
IF condition1 THEN
statements1
ELSIF condition2 THEN
statements2
ELSE
statements3
END IF;
where
condition1 and condition2 are Boolean expressions that evaluate to true or false.
statements1, statements2, and statements3 are PL/SQL statements.
This conditional logic flows as follows:
If condition1 is true, then statements1 is executed.
If condition1 is false but condition2 is true, then statements2 is executed.
If neither condition1 nor condition2 are true, then statements3 is executed.
SQL> CREATE OR REPLACE PROCEDURE cant_go_there
2 AS
3 l_salary NUMBER := 10000;
4 BEGIN
5 IF l_salary > 20000
6 THEN
7 dbms_output.put_line ('Executive');
8 ELSE
9 dbms_output.put_line ('Drone');
10 END IF;
11 END cant_go_there;
12 /
Procedure created.
SQL>
SQL> SHOW ERRORS
No errors.
SQL>
SQL> CREATE OR REPLACE PROCEDURE cant_go_there
2 AS
3 l_name varchar2(100) := 'steven';
4 BEGIN
5 IF l_name = 'STEVEN'
6 THEN
7 dbms_output.put_line ('Impossible');
8 ELSE
9 dbms_output.put_line ('Guaranteed');
10 END IF;
11 END cant_go_there;
12 /
Procedure created.
SQL>
SQL> SHOW ERRORS
No errors.
SQL>