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

[Melvin Davidson]

On Fri, Mar 25, 2016 at 11:10 AM, Igor Neyman <iney...@perceptron.com>
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. **[image:
> http://us.i1.yimg.com/us.yimg.com/i/mesg/tsmileys2/01.gif]*
>
>
>
>
>
> 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.