a wrote: > Please allow me to ask few more questions: > > 1, Since I'm writing a C trigger function, is there any method for me to get > some of the > basic information like the follow: > > (1) Total number of rows; > (2) Rows' names; > (3) Value of OLD and NEW; > > 2, Is there any possibility of passing the SQL statement it self into the > trigger? > > 3, Is it possible for me to exam before statement trigger so that I would be > able to loop it > once and copying the update information to the rest of rows.
I don't know if there is a reliable way to get the SQL statement from a C trigger. For the other things, perhaps a statement level trigger with transition relations can help. You can then access the transition relations from your C code with the tg_oldtable and tg_newtable tuplestores. (https://www.postgresql.org/docs/current/static/trigger-interface.html) Yours, Laurenz Albe -- +43-670-6056265 Cybertec Schönig & Schönig GmbH Gröhrmühlgasse 26, A-2700 Wiener Neustadt Web: https://www.cybertec-postgresql.com
