Re: Way to get at parsed trigger 'WHEN' clause expression?

[Melvin Davidson <melvin6925@xxxxxxxxx>]

On Fri, Mar 25, 2016 at 11:10 AM, Igor Neyman <ineyman@xxxxxxxxxxxxxx> wrote:

Did you mean something like

SELECT substring(pg_get_triggerdef(tg.oid, TRUE) FROM position('WHEN' in pg_get_triggerdef(tg.oid, TRUE))) AS when_cond
  FROM pg_trigger tg WHERE tg.tgname = 'your_trigger_name';

--

Melvin Davidson
I reserve the right to fantasize.  Whether or not you
wish to share my fantasy is entirely up to you.

 

 

This doesn’t answer OP question.

Besides this query gets you not only “WHEN” clause but also whatever follows it, for instance “EXECUTE PROCEDURE…”

 

As for “pg_get_expr(pg_node_tree, relation_oid)” – looks like it doesn’t work with pg_trigger, because as a second parameter (Var) it expects relation_oid, and relation could have multiple triggers, so pg_get_expr() wouldn’t know which trigger’s tgqual you want to decompile.

 

Regards,

Igor Neyman

Actually, it DOES answer the "OP" question. The "Besides" is irrelevant, as with additional length()  & position() sub functions,  just the WHEN clause can be abstracted. I'm just not going to waste my time doing all the work

when I provided a viable solution that does not error out.

--

Melvin Davidson
I reserve the right to fantasize.  Whether or not you
wish to share my fantasy is entirely up to you.