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C sql sElECt whErE

这叫做查询 一种方式 是写代码 一种方式设计视图 其实是图也是一种子查询 上代码:select * from table1 where ID in(select ID from table2 where ...) 除了in 也可以用别的运算符 如果用= > < 你得保证子查询出来的是一个值 希望我的回答对你...

sql select id from a where id=(select id from b where id=(select id from c where name='aaaaa')) 改成inner join sql select a.id from a inner join b on a.id=b.id inner join c on b.id=c.id where c.name='aaaaa'

select b. a from b where b.c like () or b.c like () and b.c like ()

select * from a where b in(‘1’ , ‘2’, ‘3’) and c '4' select * from a where b like '%1%' and b like '%2%' and b like '%3%' and c not like '%4%'

select * from a where b in(‘1’ , ‘2’, ‘3’) and c '4'

string sql = "select * from table where id in ({0})";string ids = "";foreach(var item in list){ ids+=",'"+item.ToString()+"'";}ids = ids.SubString(1);sql = string.Formart(sql,ids);

那就SQL语句需要变为动态的 declare @str varchar(100) set @str = 'select * from Table where ' + @col + '=' + @KeyWord exec(@str)

比如在Northwind数据库中有一个查询为 SELECT c.CustomerId,CompanyName FROM Customers cWHERE EXISTS(SELECT OrderID FROM Orders o WHERE o.CustomerID=c.CustomerID) 这里面的EXISTS是如何运作呢?子查询返回的是OrderId字段,可是外面的查...

例如: select * from a where b in(1 ,2,3) and c '4'

select * from [表] where [列]='' 所以选择D

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