pg_casts view (was Re: date_trun() with timezones? (was Re: TIME column ...))

Tom Lane escribió:

> However, the interval version of the function can capture the time case
> because there's an implicit cast from time to interval:
>
> regression=# select casttarget::regtype,castcontext,castfunc::regprocedure from pg_cast where castsource = 'time'::regtype;
> casttarget | castcontext | castfunc
> ------------------------+-------------+----------------------------------------
> interval | i | "interval"(time without time zone)
> time with time zone | i | timetz(time without time zone)
> time without time zone | i | "time"(time without time zone,integer)
> (3 rows)

BTW it very much looks like we should have a pg_casts view that displays
these things in a human-readable manner (like the above except with
castcontext expanded)

--
Alvaro Herrera http://www.CommandPrompt.com/
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