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Come emulare un trigger PRIMA DELETE in SQL Server 2005

È possibile utilizzare un trigger INVECE DI. Si attiva prima (sostituisce) l'effettiva eliminazione, quindi il record collegato in [uno_due] deve esistere ancora.

create table [one] (one_id int not null primary key)
create table [two] (two_id int not null primary key)
create table [one_two] (one_id int, two_id int references two(two_id) on delete cascade)
GO
CREATE trigger t_del_two
on two
instead of delete
as
begin
SET NOCOUNT ON
DECLARE @Statement NVARCHAR(max)
SET @Statement = ''
SELECT @Statement = @Statement + N'EXEC [MyProc] ''' + CAST([one_two].[one_id] AS VARCHAR(36)) + '''; '
FROM deleted
JOIN [one_two] ON deleted.[two_id] = [one_two].[two_id]

PRINT (@Statement)
--EXEC (@Statement)

-- carry out the actual delete
DELETE TWO WHERE two_id in (SELECT two_id from deleted)
end
GO

Alcuni valori di esempio

insert into one select 1
insert into one select 2
insert into one select 3
insert into two select 11
insert into two select 12
insert into two select 13
insert into one_two select 1,11
insert into one_two select 1,13
insert into one_two select 2,13

Ora provalo

delete two where two_id=13