提高查询的性能

Question

我有以下sql查询表现不好：

SELECT 
    Count(ExtCardID) as CardCount 
from 
    CardIDs CARDS with (NoLock)
inner join 
    (select CustomerPK 
     from GroupMembership with (NoLock)
     where CustomerGroupID = 14 and Deleted = 0) as GM on GM.CustomerPK = CARDS.CustomerPK

上述联接中的以下Select部分返回了800万条记录：

select 
    CustomerPK from GroupMembership with (NoLock)
where 
    CustomerGroupID = 14 and Deleted = 0

有没有更好的方法来编写上面的SQL代码？请指教。

Answer 1

你试过LINQ吗？

LINQ非常好而不是直接查询！

Great Article