触发器导致超出最大触发器嵌套级别

Question

我创建了一个新触发器，如果交付的商品数量等于订购数量，它会更新我的 [Purchase Table]，但每次运行我都会收到以下错误。

ODBC--update on a linked table 'dbo_Purchase Table' failed.
Maximum stored procedure, function, trigger or view nesting level exceeded (limit 32). (#217)

这是我创建的触发器：

USE [####]
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER TRIGGER [dbo].[trUpdatePurchaseTableStatus]
    ON [dbo].[Purchase Table]
    AFTER UPDATE
AS
    BEGIN
        SET NOCOUNT ON;
        UPDATE PT
        SET PT.Delivered = 1
        FROM inserted as I
        INNER JOIN dbo.[Purchase Table] AS PT
        ON [PT].[ID] = I.[ID]
        WHERE PT.deliveredQTY >= PT.QTY
    END

Answer 1

如果 Delivered 的值完全基于 deliveredQTY 的值是否大于或等于 QTY 我会建议改用计算列，那么您不需要不需要 TRIGGER.

您不能将现有列更改为计算列（您甚至不能 ALTER 计算列）您需要 DROP 该列然后添加它：

--You would also need to DROP any CONSTRAINTs and/or INDEXes, etc, that use the column
ALTER TABLE dbo.[Purchase Table] DROP COLUMN Delivered;
GO
ALTER TABLE dbo.[Purchase Table]
ADD Delivered AS CONVERT(bit,CASE WHEN deliveredQTY >= QTY THEN 1 ELSE 0 END) /*PERSISTED*/; --If the column is to be indexed, you'll likely want the PERSISTED
GO

Answer 2

这里真正的答案是使用计算列, .

但是，如果你真的想为此使用触发器，可以将以下代码放在顶部以提早退出

ALTER TRIGGER [dbo].[trUpdatePurchaseTableStatus]
    ON [dbo].[Purchase Table]
    AFTER UPDATE
AS

SET NOCOUNT ON;

IF TRIGGER_NESTLEVEL(OBJECT_ID('dbo.trUpdatePurchaseTableStatus')) > 1
  OR NOT EXISTS (SELECT 1 FROM inserted)
    RETURN;

UPDATE PT
..........

触发器导致超出最大触发器嵌套级别

Trigger causing Maximum trigger nesting level exceeded

sql

sql-server

sql-server-2012