使用连接的SQL更新查询

Posted 2021-04-05

我必须更新一个字段，其值由3个表的连接返回。

例：

select
    im.itemid
    ,im.sku as iSku
    ,gm.SKU as GSKU
    ,mm.ManufacturerId as ManuId
    ,mm.ManufacturerName
    ,im.mf_item_number
    ,mm.ManufacturerID
from 
    item_master im, group_master gm, Manufacturer_Master mm 
where
    im.mf_item_number like 'STA%'
    and im.sku=gm.sku
    and gm.ManufacturerID = mm.ManufacturerID
    and gm.manufacturerID=34

我想更新表mf_item_number的item_master字段值与在上述条件下连接的其他值。

我怎样才能在MS SQL Server中执行此操作？

答案

UPDATE im
SET mf_item_number = gm.SKU --etc
FROM item_master im
JOIN group_master gm
    ON im.sku = gm.sku 
JOIN Manufacturer_Master mm
    ON gm.ManufacturerID = mm.ManufacturerID
WHERE im.mf_item_number like 'STA%' AND
      gm.manufacturerID = 34

为了清楚起见...... UPDATE子句可以引用FROM子句中指定的表别名。所以im在这种情况下是有效的

Generic example

UPDATE A
SET foo = B.bar
FROM TableA A
JOIN TableB B
    ON A.col1 = B.colx
WHERE ...

另一答案

最简单的方法之一是使用公用表表达式（因为您已经在SQL 2005上）：

with cte as (
select
    im.itemid
    ,im.sku as iSku
    ,gm.SKU as GSKU
    ,mm.ManufacturerId as ManuId
    ,mm.ManufacturerName
    ,im.mf_item_number
    ,mm.ManufacturerID
    , <your other field>
from 
    item_master im, group_master gm, Manufacturer_Master mm 
where
    im.mf_item_number like 'STA%'
    and im.sku=gm.sku
    and gm.ManufacturerID = mm.ManufacturerID
    and gm.manufacturerID=34)
update cte set mf_item_number = <your other field>

查询执行引擎将自己弄清楚如何更新记录。

另一答案

将其改编为mysql - FROM中没有UPDATE子句，但这有效：

UPDATE
    item_master im
    JOIN
    group_master gm ON im.sku=gm.sku 
    JOIN
    Manufacturer_Master mm ON gm.ManufacturerID=mm.ManufacturerID
SET
    im.mf_item_number = gm.SKU --etc
WHERE
    im.mf_item_number like 'STA%'
    AND
    gm.manufacturerID=34

另一答案

没有使用上面的sql，但这里是一个基于join语句更新表的示例。

UPDATE p
SET    p.category = c.category
FROM   products p
       INNER JOIN prodductcatagories pg
            ON  p.productid = pg.productid
       INNER JOIN categories c
            ON  pg.categoryid = c.cateogryid
WHERE  c.categories LIKE 'whole%'

另一答案

您可以使用UPDATE语句中的“FROM”子句指定用于确定更新方式和更新内容的其他表，如下所示：

update item_master
set mf_item_number = (some value)
from 
   group_master as gm
   join Manufacturar_Master as mm ON ........
where
 .... (your conditions here)

在WHERE子句中，您需要提供条件和连接操作以将这些表绑定在一起。

渣

另一答案

MySQL: In general, make necessary changes par your requirement:

UPDATE
    shopping_cart sc
    LEFT JOIN
    package pc ON sc. package_id = pc.id    
SET
    sc. amount = pc.amount

另一答案

试试这样......

Update t1.Column1 = value 
from tbltemp as t1 
inner join tblUser as t2 on t2.ID = t1.UserID 
where t1.[column1]=value and t2.[Column1] = value;

另一答案

您可以使用以下查询：

UPDATE im
SET mf_item_number = (some value) 
FROM item_master im
JOIN group_master gm
    ON im.sku = gm.sku 
JOIN Manufacturer_Master mm
    ON gm.ManufacturerID = mm.ManufacturerID
WHERE im.mf_item_number like 'STA%' AND
      gm.manufacturerID = 34    `sql`

另一答案

您可以使用MERGE命令更新MATCHED和NOT MATCHED :(稍微更改了源代码以证明我的观点）

USE tempdb;
GO
IF(OBJECT_ID('target') > 0)DROP TABLE dbo.target
IF(OBJECT_ID('source') > 0)DROP TABLE dbo.source
CREATE TABLE dbo.Target
    (
      EmployeeID INT ,
      EmployeeName VARCHAR(100) ,
      CONSTRAINT Target_PK PRIMARY KEY ( EmployeeID )
    );
CREATE TABLE dbo.Source
    (
      EmployeeID INT ,
      EmployeeName VARCHAR(100) ,
      CONSTRAINT Source_PK PRIMARY KEY ( EmployeeID )
    );
GO
INSERT  dbo.Target
        ( EmployeeID, EmployeeName )
VALUES  ( 100, 'Mary' );
INSERT  dbo.Target
        ( EmployeeID, EmployeeName )
VALUES  ( 101, 'Sara' );
INSERT  dbo.Target
        ( EmployeeID, EmployeeName )
VALUES  ( 102, 'Stefano' );

GO
INSERT  dbo.Source
        ( EmployeeID, EmployeeName )
VALUES  ( 100, 'Bob' );
INSERT  dbo.Source
        ( EmployeeID, EmployeeName )
VALUES  ( 104, 'Steve' );
GO

SELECT * FROM dbo.Source
SELECT * FROM dbo.Target

MERGE Target AS T
USING Source AS S
ON ( T.EmployeeID = S.EmployeeID )
WHEN MATCHED THEN
    UPDATE SET T.EmployeeName = S.EmployeeName + '[Updated]';
GO 
SELECT '-------After Merge----------'
SELECT * FROM dbo.Source
SELECT * FROM dbo.Target