sql - SQL查询-如何同时使用exist和not exist条件

Question

我有两张桌子TableA和TableB. TableA有一列newValue和oldValue。TableB有一列value。

我想要以下结果：从TableA其中newValue存在TableB和oldValue不存在的地方获取所有行TableB。

两个表都有很多行，所以性能很重要！

您将如何在 SQL Server 2010/2012 中实现这一点？

（ui：我没有找到这个问题的属性标题）。

编辑：

我尝试的第一件事是：

SELECT newValue, oldValue
FROM TableA
WHERE newValue IN (SELECT value FROM TableB) 
  AND oldValue NOT IN (SELECT value FROM Table B)

但这效率低下，并且在我的数据库上性能很差。我正在寻找其他解决方案。

Answer 1

我认为在这里避免EXISTS并IN有助于提高速度：

SELECT
        *
    FROM TableA
    WHERE
        (SELECT TOP 1 1 FROM TableB WHERE value = newValue) IS NOT NULL
        AND
        (SELECT TOP 1 1 FROM TableB WHERE value = oldValue) IS NULL

Answer 2

你可以存在使用存在/不存在

SELECT newValue, oldValue
FROM TableA as t1 
where exists(SELECT value FROM TableB as t2 where t1.newValue=t2.value) and 
 not exists(SELECT value FROM TableB as t3 where t1.olvalue=t3.value)

Answer 3

如果你在value,newvalue和上有索引oldvalue，你可以试试这个：

select
    a.newValue, a.oldValue
from TableA as a
where
    a.newValue in (select distinct b.value from TableB as b) and
    a.oldValue not in (select distinct b.value from TableB as b)

或exists：

select
    a.newValue, a.oldValue
from TableA as a
where
    exists (select * from TableB as b where b.value = a.newValue) and
    not exists (select * from TableB as b where b.value = a.oldValue)

Answer 4

您可以使用单一存在条件来执行此操作。

 SELECT newValue, oldValue
 FROM TableA a
 WHERE exists 
 (
  SELECT 1 FROM TableB b 
  where a.newValue = b.value 
  and a.oldValue != b.value)

Answer 5

Select Distinct A.*
From TableA A
     Inner Join TableB B on A.newValue = B.Value
Where A.OldValue NOT In (Select Value From TableB)

Answer 6

请试试：

select * from TableA where newValue in (select value from TableB)
union
select * from TableA where oldValue not in (select value from TableB)