摘要:
下文讲述sqlserver中使用join替换in关键字的方法分享,如下所示:
实验环境:sql server 2008 R2
---in 关键字的写法 SELECT count(1) FROM tableNameA a WHERE a.keyId not IN( SELECT keyId FROM tableNameB as b WHERE b.info ='test' ) ---转换为join关键字 SELECT count(1) FROM tableNameA a join tableNameB b on a.keyId = b.keyId WHERE b.info <>'test' ---in 关键字写法 SELECT count(*) FROM tableNameA a WHERE keyId IN ( SELECT keyId FROM tableNameB b WHERE b.info ='test' ) ---join 关键字转发 SELECT count(1) FROM tableNameA a join tableNameB b on a.keyId = b.keyId WHERE b.info ='test'