使用 MERGE 在单个语句中对表执行 UPDATE 和 DELETE 操作
- 作者: xiao_8
- 来源: 51数据库
- 2022-08-17
USE AdventureWorks2012; GO IF OBJECT_ID (N'Production.usp_UpdateInventory', N'P') IS NOT NULL DROP PROCEDURE Production.usp_UpdateInventory; GO CREATE PROCEDURE Production.usp_UpdateInventory @OrderDate datetime AS MERGE Production.ProductInventory AS target USING (SELECT ProductID, SUM(OrderQty) FROM Sales.SalesOrderDetail AS sod JOIN Sales.SalesOrderHeader AS soh ON sod.SalesOrderID = soh.SalesOrderID AND soh.OrderDate = @OrderDate GROUP BY ProductID) AS source (ProductID, OrderQty) ON (target.ProductID = source.ProductID) WHEN MATCHED AND target.Quantity - source.OrderQty <= 0 THEN DELETE WHEN MATCHED THEN UPDATE SET target.Quantity = target.Quantity - source.OrderQty, target.ModifiedDate = GETDATE() OUTPUT $action, Inserted.ProductID, Inserted.Quantity, Inserted.ModifiedDate, Deleted.ProductID, Deleted.Quantity, Deleted.ModifiedDate; GO EXECUTE Production.usp_UpdateInventory '20030501'
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