m0_46608027的博客

mybatis的练习 <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.dhc.batis.dao.UserDao"> <select id="queryUserList" resultType="com.dhc.batis.mo

SELECT emptab.* FROM emptab WHERE empage = ( SELECT MAX(EMPAGE) AS MAX_EMPAGE FROM emptab ) SELECT MAX(EMPAGE) , T.empid FROM emptab T GROUP BY T.empid – 查询每个部门中年龄最大的员工信息 SELECT T1.departid , T1.empid , T1.empnm , T1.empage , T1.salary FROM emptab T1 INNER