Oct15

想把COUNT放到where子句中？

October 15th, 2007 in Technology

嘿嘿，这就说明你的数据库课没有学好…… 　　错误做法：select * from user_num where count(user)>＝2 group by user; 　　正确做法：select * from user_num group by user HAVING count(user)>＝2 ; 用having子句吧！...

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