Sub programs are named PL/SQL blocks that can take parameters and be invoked. There are two types: procedures, which perform actions, and functions, which perform actions and return a value. Functions can be either local, defined in the declaration section, or stored directly in the Oracle engine.

1. SUB PROGRAMS
Sub programs are the named PL SQL blocks that can take parameters and can be invoked.
Types:
Procedures
Functions
Function-
Functions are like procedures that perform action. The only difference is that functions
return a value.
Types: local and stored
1. Local functions- That are defined in declaration section of the program.
Example:-
SQL> ed great
Declare
A number;
B number;
Result number;
Function great (A number, B number) return number
As
C number;
Begin
C=A*B
Return(C);
End product;
Begin
A:= &A;
B:= &B;
Result:= great(A,B);

2. dbms_output.put_line(‘product =’ ||result);
end;
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2. Stored functions- that are stored in oracle engine.
Example:-
SQL> ed great
Create or replace function great (A number, B number, C number) return number
As
Begin
If (A>B and A>C) then
Return A;
Elsif (A<B and C<B) then
Return B;
Else
Return C;
Endif;
End great;
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