觸發更新 SQL 服務器表

Question

我想為 SQL 服務器表的特定條件更新一個列值。 我有以下用於創建表的代碼

CREATE TABLE [dbo].[EQUIPMENT](
 [ID] [int] IDENTITY(10000,1) NOT NULL,
 [Equipment] [nvarchar](80) NOT NULL,
 [Facility] [nvarchar](40) NULL,
 [EquipmentType] [smallint] NULL,
 [Active] [bit] NOT NULL)

以下是插入和更新語句

INSERT INTO [Equipment] ([Equipment],[Facility],[EquipmentType],[Active]) VALUES ('E02','1029',10,1)
UPDATE [Equipment] Set Active = 0 where [Equipment] = 'E01'

以下是觸發腳本

CREATE TRIGGER dbo.ATRG_EquipmentTypeUpdate
ON [dbo].[Equipment]
AFTER INSERT, UPDATE
AS 
BEGIN   
   SET NOCOUNT ON;

   -- update your table, using a set-based approach
   -- from the "Inserted" pseudo table which CAN and WILL
   -- contain multiple rows!
   UPDATE [dbo].[Equipment] 
   SET  EquipmentType  = 15 
   FROM Inserted i
   WHERE [dbo].[Equipment].ID = i.ID
   AND [dbo].[Equipment].EquipmentType = 10
END
GO

當我嘗試運行 Insert OR update 語句時 - 我有以下錯誤。

Msg 217, Level 16, State 1, Procedure ATRG_EquipmentTypeUpdate1, Line 12 [Batch Start Line 9]
Maximum stored procedure, function, trigger, or view nesting level exceeded (limit 32).

任何機構都可以提供建議嗎？ 表中還有其他三個觸發器。 這個，我需要作為臨時解決方案，用於解決方法。

Answer 1

除非您選擇加入Recursive Triggers ，否則更新其表的觸發器不會再次觸發，因此請檢查 RECURSIVE TRIGGERS 數據庫設置，如果已打開，請將其關閉：

alter database current set recursive_triggers off

或者將您的觸發器編碼為不執行零行的更新，例如

if not exists (select * from inserted) return

Answer 2

您可以使用TRIGGER_NESTLEVEL檢查遞歸調用。

您還應該檢查inserted的行中是否沒有行。

CREATE TRIGGER dbo.ATRG_EquipmentTypeUpdate
ON [dbo].[Equipment]
AFTER INSERT, UPDATE
AS 
BEGIN
   SET NOCOUNT ON;

   IF TRIGGER_NESTLEVEL(OBJECT_ID('dbo.ATRG_EquipmentTypeUpdate', 'AFTER', 'DML')) > 1
      OR NOT EXISTS (SELECT 1 FROM inserted)
       RETURN;

   -- update your table, using a set-based approach
   -- from the "Inserted" pseudo table which CAN and WILL
   -- contain multiple rows!
   UPDATE 
   SET EquipmentType = 15 
   FROM Inserted i
   JOIN [dbo].[Equipment] e ON e.ID = i.ID
     AND e.EquipmentType = 10;
END

還要注意在更新中使用正確的JOIN語法。