mysql 语句case when

select USER_ID ,USER_NAME ,CASE WHEN  atten.DESTINATION_ID is null THEN FALSE ELSE TRUE END  as attentioned    from T_SD_USER as user LEFT OUTER JOIN T_SD_ATTENTION as atten on `user`.USER_ID = atten.ORIGIN_ID and atten.DESTINATION_ID = 3001 where `user`.USER_ID = 3000;

表的创建

CREATE TABLE `lee` (
`id` int(10) NOT NULL AUTO_INCREMENT, 
`name` char(20) DEFAULT NULL, 
`birthday` datetime DEFAULT NULL, 
PRIMARY KEY (`id`)) ENGINE=InnoDB DEFAULT CHARSET=utf8

数据插入：

insert into lee(name,birthday) values (‘sam‘,‘1990-01-01‘);

insert into lee(name,birthday) values (‘lee‘,‘1980-01-01‘);

insert into lee(name,birthday) values (‘john‘,‘1985-01-01‘);

使用case when语句

1。

来自 http://www.cnblogs.com/john2000/archive/2010/09/21/1832729.html

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