select * from tablename where 1=0的意义
2014-05-10 20:19
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select * from tablename where 1=0的意义
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1=0在SQL中是不成立的条件,返回值也就是"假"
此语句的作用是:
打开此记录集,但并不从记录集中读取任何记录
直观点说就是,为保护记录集数据,仅做打开,是只做插入记录时用到
==================================================
1=0在SQL中是不成立的条件,返回值也就是"假"
此语句的作用是:
打开此记录集,但并不从记录集中读取任何记录
直观点说就是,为保护记录集数据,仅做打开,是只做插入记录时用到
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