![PL/SQL Function
âĸ The PL/SQL Function is very similar to PL/SQL Procedure.
âĸ The main difference between procedure and a function is, a function must
always return a value, and on the other hand a procedure may or may not
return a value.
âĸ Syntax to create a function:
âĸ CREATE [OR REPLACE] FUNCTION function_name [parameters]
âĸ [(parameter_name [IN | OUT | IN OUT] type [, ...])]
âĸ RETURN return_datatype
âĸ {IS | AS}
âĸ BEGIN
âĸ < function_body >
âĸ END [function_name];](https://image.slidesharecdn.com/two-230824155406-315a7915/85/TWO-pptx-7-320.jpg)
![âĸ Here:
âĸ Function_name: specifies the name of the function.
âĸ [OR REPLACE] option allows modifying an existing function.
âĸ The optional parameter list contains name, mode and types of the
parameters.
âĸ IN represents that value will be passed from outside and OUT
represents that this parameter will be used to return a value outside
of the procedure.](https://image.slidesharecdn.com/two-230824155406-315a7915/85/TWO-pptx-8-320.jpg)
TWO.pptx
- 2. Syntax for IF Statement: âĸ IF condition âĸ THEN âĸ Statement: {It is executed when condition is true} âĸ END IF; âĸ There are different syntaxes for the IF-THEN-ELSE statement.
- 3. âĸ IF condition âĸ THEN âĸ {...statements to execute when condition is TRUE...} âĸ ELSE âĸ {...statements to execute when condition is FALSE...} âĸ END IF;
- 4. âĸ Syntax: (IF-THEN-ELSIF statement): âĸ IF condition1 âĸ THEN âĸ {...statements to execute when condition1 is TRUE...} âĸ ELSIF condition2 âĸ THEN âĸ {...statements to execute when condition2 is TRUE...} âĸ END IF;
- 5. Syntax: (IF-THEN-ELSIF-ELSE statement): âĸ IF condition1 âĸ THEN âĸ {...statements to execute when condition1 is TRUE...} âĸ ELSIF condition2 âĸ THEN âĸ {...statements to execute when condition2 is TRUE...} âĸ ELSE âĸ {...statements to execute when both condition1 and condition2 are FALSE ...} âĸ END IF;
- 6. âĸ DECLARE âĸ a number(3) := 500; âĸ BEGIN âĸ -- check the boolean condition using if statement âĸ IF( a < 20 ) THEN âĸ -- if condition is true then print the following âĸ dbms_output.put_line('a is less than 20 ' ); âĸ ELSE âĸ dbms_output.put_line('a is not less than 20 ' ); âĸ END IF; âĸ dbms_output.put_line('value of a is : ' || a); âĸ END;
- 7. PL/SQL Function âĸ The PL/SQL Function is very similar to PL/SQL Procedure. âĸ The main difference between procedure and a function is, a function must always return a value, and on the other hand a procedure may or may not return a value. âĸ Syntax to create a function: âĸ CREATE [OR REPLACE] FUNCTION function_name [parameters] âĸ [(parameter_name [IN | OUT | IN OUT] type [, ...])] âĸ RETURN return_datatype âĸ {IS | AS} âĸ BEGIN âĸ < function_body > âĸ END [function_name];
- 8. âĸ Here: âĸ Function_name: specifies the name of the function. âĸ [OR REPLACE] option allows modifying an existing function. âĸ The optional parameter list contains name, mode and types of the parameters. âĸ IN represents that value will be passed from outside and OUT represents that this parameter will be used to return a value outside of the procedure.
- 9. âĸ The function must contain a return statement. âĸ RETURN clause specifies that data type you are going to return from the function. âĸ Function_body contains the executable part. âĸ The AS keyword is used instead of the IS keyword for creating a standalone function.
- 10. âĸ create or replace function adder(n1 in number, n2 in number) âĸ return number âĸ is âĸ n3 number(8); âĸ begin âĸ n3 :=n1+n2; âĸ return n3; âĸ end; âĸ /
- 11. âĸ DECLARE âĸ n3 number(2); âĸ BEGIN âĸ n3 := adder(11,22); âĸ dbms_output.put_line('Addition is: ' || n3); âĸ END; âĸ /