Question

我是SQL Server新手，需要帮助才能完成存储过程。这是代码：

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO

IF OBJECT_ID('spCopyPurchaseOrders') IS NOT NULL
    DROP PROC spCopyPurchaseOrders;

GO

CREATE PROC spCopyPurchaseOrders
AS

    IF OBJECT_ID('PurchaseOrders') IS NOT NULL
        DROP TABLE PurchaseOrders;
    SELECT *
    INTO PurchaseOrdersCopy
    FROM PurchaseOrders;

即使脚本顶部有一个有效的USE语句，我也无法识别数据库。有什么想法吗？

Answer 1

在编码时，PurchaseOrders表在SELECT

之前被删除

IF OBJECT_ID('PurchaseOrders') IS NOT NULL
    DROP TABLE PurchaseOrders;   -- <<< this breaks the SELECT FROM
SELECT *
INTO PurchaseOrdersCopy   
FROM PurchaseOrders;   -- <<< can't possible exist, the IF...DROP saw to it

由于您使用的是SELECT...INTO，因此您可能需要PurchaseOrdersCopy

但是，这会更好

 -- create an empty table, but just once, otherwise empty the existing table
IF OBJECT_ID('dbo.PurchaseOrdersCopy') IS NULL
   SELECT *
    INTO dbo.PurchaseOrdersCopy   
    FROM dbo.PurchaseOrders 
    WHERE 1=0 
ELSE IF EXISTS (SELECT * FROM dbo.PurchaseOrdersCopy  )
   DELETE FROM dbo.PurchaseOrdersCopy; -- HINT: see if TRUNCATE TABLE dbo.PurchaseOrdersCopy is an option for you

-- this will be longer if you have an IDENTITY column
-- SET IDENTITY_INSERT ON (for example)
INSERT INTO dbo.PurchaseOrdersCopy   
SELECT *
FROM dbo.PurchaseOrders;

具体做法是：

a）尝试并在可以

时避免DROP和CREATE

b）使用架构名称（默认为dbo.）为对象名称添加前缀

关注：如果程序可以多次运行或由多人运行（dbo.PurchaseOrdersCopy共享），这将如何工作

试图结束存储过程

1 个答案: