zoukankan      html  css  js  c++  java
  • MySQL 函数

    一、case 【列名称】 when【条件】 then 【返回值】... else 【返回值】end

    1、简单单一条件

    SELECT
    	CASE o.operate_status
    	  WHEN '1' THEN '暂停'
    	  WHEN '2' THEN '启用'
    	  WHEN '3' THEN '失效'
    	  ELSE '其他' END AS operate_status,
    	o.change_reason,
    	o.creator_name,
    	DATE_FORMAT(o.operate_time, '%Y-%m-%d %H:%i') AS operate_time
    FROM [tablName] AS o
    WHERE o.operate_status in ('1', '2', '3', '4', '5')  

    查询效果:

    2、多个条件

    SELECT
    	CASE o.operate_status
    	  WHEN '1' OR '2' THEN '编制'
    	  WHEN '3' OR '4' THEN '编制'
    	  WHEN '5' THEN '暂停'
    	  WHEN '6' THEN '启用'
    	  WHEN '7' THEN '失效'
    	  ELSE '其他' END AS operate_status,
    	CASE o.operate_status
    	  WHEN '1' THEN '暂存信息'
    	  WHEN '2' THEN '提交'
    	  WHEN '3' THEN '审核通过'
    	  WHEN '4' THEN '审核不通过'
    	  WHEN '5' THEN '暂停'
    	  WHEN '6' THEN '启用'
    	  WHEN '7' THEN '失效'
    	  ELSE '其他' END AS operate_result,
    	o.change_reason,
    	o.creator_name,
    	DATE_FORMAT(o.operate_time, '%Y-%m-%d %H:%i') AS operate_time
    FROM [tableName] AS o
    WHERE o.operate_status in ('1', '2', '3', '4', '5')
    

    查询效果如下: 

    二、case [ when 【条件】then【返回值】... else 【返回值】end ]

    SELECT 
    	CASE 
    	  WHEN o.operate_status = '1' OR o.operate_status = '2' THEN '编制'
    	  WHEN o.operate_status = '3' OR o.operate_status = '4' THEN '编制'
    	  WHEN o.operate_status = '5' THEN '暂停'
    	  WHEN o.operate_status = '6' THEN '启用'
    	  WHEN o.operate_status = '7' THEN '失效'
    	  ELSE '其他' END AS operate_status,
    	o.change_reason,
    	o.creator_name,
    	DATE_FORMAT(o.operate_time, '%Y-%m-%d %H:%i') AS operate_time
    FROM [tableName] AS o
    WHERE o.operate_status in ('1', '2', '3', '4', '5');

    查询效果如下:

  • 相关阅读:
    自定义 Repository 方法
    SpringData_JpaSpecificationExecutor接口
    SpringData_JpaRepository接口
    SpringData_PagingAndSortingRepository接口
    SpringData_CrudRepository接口
    SpringData修改和删除操作
    自定义查询语句SpringData
    SpringData关键字查询练习
    compile——生成ast
    vue-compile概述
  • 原文地址:https://www.cnblogs.com/yuchuan/p/mysql_case_when.html
Copyright © 2011-2022 走看看