The IF-THEN-ELSIF statement allows you to choose between several alternatives. An IF-THEN statement can be followed by an optional ELSIF...ELSE statement. The ELSIF clause lets you add additional conditions.
When using IF-THEN-ELSIF statements there are a few points to keep in mind.
It's ELSIF, not ELSEIF.
An IF-THEN statement can have zero or one ELSE's and it must come after any ELSIF's.
An IF-THEN statement can have zero to many ELSIF's and they must come before the ELSE.
Once an ELSIF succeeds, none of the remaining ELSIF's or ELSE's will be tested.
The syntax of an IF-THEN-ELSIF Statement in PL/SQL programming language is −
IF(boolean_expression 1)THEN S1; -- Executes when the boolean expression 1 is true ELSIF( boolean_expression 2) THEN S2; -- Executes when the boolean expression 2 is true ELSIF( boolean_expression 3) THEN S3; -- Executes when the boolean expression 3 is true ELSE S4; -- executes when the none of the above condition is true END IF;
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; /
When the above code is executed at the SQL prompt, it produces the following result −
None of the values is matching Exact value of a is: 100 PL/SQL procedure successfully completed.