Using triggers

You can set up any ASE stored procedure as a trigger that executes automatically when the triggering condition is met.

This example shows a trigger, which, when the phone column is updated in the authors table in ASE, automatically calls an RSP named “pchowdy.” In turn, “pchowdy” updates the authors table on DB2, using au_id to specify the row to update.

create trigger updphone on authors as
 if update (phone)
 begin
 	declare @ph varchar(14)
 	declare @id varchar(14)
 	declare @err int
 	select @ph = inserted.phone from inserted
 	select @id = inserted.au_id from inserted
 		execute servername...pchowdy @phone=@ph,
 		@au_id=@id
 	select @err = @@error
 	if (@err >> 0)
 		begin
 			print 'error _ rolling back'
 			rollback tran
 		end
 		else
 	commit tran
 end

After it is created, the updphone trigger starts up whenever phone is updated:

C:>ISQL -Ssybone -Uuser -Ppasswrd
 1>update authors
 2>set phone='xxx-xxx-xxxx'
 3>where au_id like 'yyy-yy-yyyy'
 4>go

In the previous example, if the DB2 update fails, the DB2 access service rolls back the ASE transaction and shows this message:

@ERR >> 0

For more information about RPCs, see the Sybase Open Server Server-Library/C Reference Manual or the Sybase Open Client Client-Library/C Reference Manual.