Oracle PLSQL function is a named block which can return a value. Oracle PLSQL allows us to create functions to meet various business needs. PLSQL functions are also called as subroutines or subprograms. Oracle PLSQL syntax to create a function is: CREATE [OR REPLACE] FUNCTION function_name [( parameter_1 [IN] [OUT] parameter_data_type_1, parameter_2 [IN] [OUT] parameter_data_type_2,… […]