Question

寻找SQL查询来执行以下操作：

将x的{{1}}列的所有值插入table1的列y，如果表2中不存在它们

table2

从列table2删除记录 y

x

我尝试插入或忽略插入查询而在sql server 2008 R2中没有运气

Answer 1

听起来非常适合SQL Server MERGE;

MERGE table2 AS t2
USING table1 AS t1
ON (t2.y = t1.x)
WHEN NOT MATCHED BY TARGET 
  THEN INSERT (y) VALUES(t1.x)
WHEN NOT MATCHED BY SOURCE
  THEN DELETE;

An SQLfiddle to test with

Answer 2

这会将Table1，colX中的所有记录插入Table2，colY：

INSERT INTO Table2 (ColY)
SELECT ColX 
FROM Table1
WHERE ColX NOT IN (SELECT ColY FROM Table2)

您无法删除列中的所有记录。但是，您可以将它们设置为NULL，或者如果要删除行，也可以执行此操作。请告诉我们。

DELETE FROM Table2
WHERE ColY NOT IN (SELECT ColX From Table1)

OR

UPDATE Table2
SET ColY = NULL
WHERE ColY NOT IN (SELECT ColX From Table1)

祝你好运。

Answer 3

您可以使用Merge Statement

MERGE table2 AS t2
USING table1 AS t1
ON (t2.y = t1.x) 
WHEN NOT MATCHED BY TARGET 
    THEN INSERT(y) VALUES(t1.x)
WHEN NOT MATCHED BY SOURCE
    THEN DELETE 
OUTPUT $action, inserted.*, deleted.*;

如果存在则删除sql如果两个表之间不存在则删除

3 个答案: