SQLトリガー - フィールドは

Question

を変更したかどうかを判断私はこのトリガー

ALTER TRIGGER [dbo].[tInsertTaskFromOpportunityReassignment] 
    ON [dbo].[OpportunityBase] 
    FOR UPDATE 
AS 
BEGIN 

IF UPDATE(owninguser) 
BEGIN 
-- do the task 
END 
END 

を持っている私はowninguserが実際に変更された場合は、タスクをやりたいです。それをどうやって決めることができますか？

おかげ

Answer 1

ALTER TRIGGER [dbo].[tInsertTaskFromOpportunityReassignment] 
    ON [dbo].[OpportunityBase] 
    FOR UPDATE 
AS 
BEGIN 
DECLARE HasChanged int = 0; 

SELECT @HasChanged = 1 
FROM Inserted AS I 
INNER JOIN Deleted AS D 
ON I.PK = D.PK 
AND IsNull(I.owninguser,'~') <> IsNull(D.owninguser,'~') 

IF @HasChanged = 1 
BEGIN 
-- do the task 
END 
END 

は、主キーに2つのテーブルを結合、挿入、削除間のフィールドの値を比較します。

Answer 2

ALTER TRIGGER [dbo].[tInsertTaskFromOpportunityReassignment] 
    ON [dbo].[OpportunityBase] 
    FOR UPDATE 
AS 
BEGIN 
/* 
    I will assume that your [dbo].[OpportunityBase] table has a PRIMARY KEY 
    or UNIQUE column that is immutable to join the inserted and deleted 
    tables. In this example, [OpportunityBaseId] is that column. 

    The SELECT query returns a set of all records that had the value of [owninguser] 
    changed. What you would do from that point is up to you. 
*/ 
SELECT 
    i.[OpportunityBaseId], i.owninguser New_owninguser, d.owninguser Old_owninguser 
FROM inserted i 
JOIN deleted d 
    ON i.[OpportunityBaseId] = d.[OpportunityBaseId] 
    AND 
     (
      --owninguser value was changed. 
      i.[owninguser] <> d.[owninguser] OR 

      --owninguser changed from non-NULL to NULL. 
      (i.[owninguser] IS NULL AND d.[owninguser] IS NOT NULL) OR 

      --owninguser changed from NULL to non-NULL. 
      (i.[owninguser] IS NOT NULL AND d.[owninguser] IS NULL) 
     ) 
END 
GO