01 2019 档案
摘要:结果为: 表A和表B是1对多的关系 A.ID => B.AID SELECT ID,NAME FROM A WHERE EXIST (SELECT * FROM B WHERE A.ID=B.AID) 执行结果为 1 A1 2 A2 原因可以按照如下分析 SELECT ID,NAME FROM A
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摘要:MySQL: select * from tableName where name like '%helloworld%'; Oracle:select * from tableName where instr(name,'helloworld')>0; select BLACK_VALUE, COUNT(*)as total from EC_COUPONS_BLACK ...
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