CREATE OR REPLACE FUNCTION
CREATE OR REPLACE FUNCTION totalCustomers RETURN number IS total number(2) := 0; BEGIN SELECT count(*) into total FROM customers; RETURN total; END; /
Source: www.tutorialspoint.com
CREATE OR REPLACE FUNCTION
CREATE [OR REPLACE] FUNCTION function_name [(parameter_name [IN | OUT | IN OUT] type [, ...])] RETURN return_datatype {IS | AS} BEGIN < function_body > END [function_name];
Source: www.tutorialspoint.com