(not studentr.date is null),SQL
(not studentr.date is null),SQL
SQL中IS NOT NULL与!=NULL是等价的吗
SQL中,下列空操作不正确的是 A.AGE IS NULL B.AGE IS NOT NULL C.AGE = NULL
sql is not null 怎么会把空的数据也查出来
请问下面这段代码sql="id is not null"和下面的sql=sql&" and……怎么理解?
Is Not Null 是什么
payment_no is not allow null
GROUP BY ROLLUP (A,B,C) HAVING A IS NOT NULL AND D NOT NULL是
数据库中语句is not null和!=null有什么区别?
the specified call count is not a number:null
photo_x is not null or photo_x''的问题
payment_no is not allow null 给翻译下