十6、子查詢與關聯查詢

                                     子查詢與關聯查詢 一、子查詢 1.一、單行子查詢 select * from emp where sal = (select sal from emp where empno = 7876); 1.二、多行子查詢 多行子查詢 any： select * from emp where sal > any(select avg

>>阅读原文<<