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Cómo emular un activador ANTES DE ELIMINAR en SQL Server 2005

Puede usar un disparador INSTEAD OF. Se activa antes (reemplaza) la eliminación real, por lo tanto, el registro vinculado en [uno_dos] aún debe existir.

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

Algunos valores de muestra

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

Ahora pruébalo

delete two where two_id=13