Question

也许我错过了一个支架或者其他东西，但是我很难从表格变量中删除行，而我正在加入并寻找我正在加入的密钥。如果它有一个值，那么我就摆脱它了。问题是我无法解析查询。有什么想法吗？

声明@MrTemp （ key1 int ，key2 int ）

插入@MrTemp 从ASourceTable中选择key1，key2

删除
来自@MrTemp山在mt.key1 = art.key1和mt.key2 = art.key2上左连接ARealTable art 其中art.key1不为null且art.key2不为null

Answer 1

DELETE @MrTemp
FROM @MrTemp mt LEFT JOIN ...

Answer 2

您一次只能从一个表中删除：

从@MrTemp中删除[其中ARealTable中有匹配的记录]

delete mt
from @MrTemp mt left join ARealTable art on mt.key1 = art.key1 and mt.key2 = art.key2 where art.key1 is not null and art.key2 is not nu

LL

或。从ARealTable中删除[再次记录在ARealTable中有相应的记录]

delete art
from @MrTemp mt left join ARealTable art on mt.key1 = art.key1 and mt.key2 = art.key2 where art.key1 is not null and art.key2 is not null

Answer 3

您需要在删除后但在要从

删除的表的from之前引用别名

delete art 
from @MrTemp mt left join ARealTable art on 
mt.key1 = art.key1 and mt.key2 = art.key2 
where art.key1 is not null and art.key2 is not null

使用左连接和表变量删除

3 个答案: