Question

I’m creating a trigger on one table which should update date_modified column. Is below code the best approach to do this? Am I doing this right?

IF EXISTS(SELECT * FROM DELETED) --checking if this is an update, not insert
BEGIN
IF NOT(UPDATE(date_modified)) -- checking if desired column was not updated
BEGIN
    DECLARE @updatedID int
    SELECT @updatedID = ID FROM deleted -- fetching updated record ID
    UPDATE table SET date_modified=GETDATE() WHERE ID=@updatedID -- updating desired column
END

Answer 1

You can simply use this instead of declaring variable

UPDATE table SET date_modified=GETDATE() WHERE ID in 
(SELECT ID FROM deleted)