條款五十九，嘗試使用 RETURNING INTO，而非使用 Using OUT 綁定輸出參數。 像是下面這段程式使用了 Using OUT 語法去綁定輸出參數就不被建議。 CREATE OR REPLACE PACKAGE BODY employee_api IS PROCEDURE upd_salary (in_employee_id IN employees.employee_id%TYPE ,in_increase_pct IN types_up.percentage ,out_new_salary OUT employees.salary%TYPE) IS co_sql_stmt CONSTANT types_up.big_string_type := ' UPDATE employees SET salary = salary + (salary / 100 * :1) WHERE employee_id = :2 RETURNING salary INTO :3'; BEGIN EXECUTE IMMEDIATE co_sql_stmt USING in_increase_pct, in_employee_id, OUT out_new_salary; END upd_salary; END employee_api; / 建議的做法是用 RETURNING INTO 語法去綁定輸出參數。