I got it:


CREATE TRIGGER TR_TRANSACTION_INSERT ON [dbo].[Transaction]
INSTEAD OF INSERT
AS

BEGIN

Declare @Quart int, @DhCreation datetime

SELECT @DhCreation = DhCreation FROM INSERTED
SET @Quart = dbo.GetQuartID(@DhCreation)


INSERT INTO [Transaction] (DhCreation, QuartID) values (@DhCreation,@Quart)

END



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IT SEEMS that a SELECT is required and that the inserted by itself is not valid..


Thanks.