exists是什么意思啊exists(select * from WE_Contract_Detail_Electricity where ContractID=@ContractID)

exists是什么意思 exists No catalogue exists是什么意思 exists是什么意思啊exists(select * from WE_Contract_Detail_Electricity where ContractID=@ContractID) user does not exists是什么意思 user does not exists这是什么意思? There exists .There exists 后面接的词是主语还是宾语?就说There exists (I/me)?exist+8+s oracle中EXISTS是什么意思我是新手 急求答案 谢谢 请问“A file with that name already exists”是什么意思? the top half——already exists是什么意思 EXISTS意思yisi111122222 exists怎么读 User does not exists user does not exists! No socket exists user does not exists翻译 魔兽世界宏[@mouseover,exists,help] [@target,exists,help] [@targettarget,exists,help] [@player]求具体说明, if not exists (SELECT * From TA_ARTIFICER Where ARTID = @Artid)是什么意思?为什么要用到if not exists呢?在什么时候要用到 if not exists（）?它的作用是什么?