Re: SHOW ALL as a query result

Christopher Kings-Lynne wrote:
> Hi All,
>
> Now that Tom's modified the EXPLAIN output to appear as a query
> result, maybe SHOW and SHOW ALL should also be modified in that way.
> The current NOTICE: business is a bit messy, and it sure would
> assist projects just as pgAccess, phpPgAdmin and pgAdmin with
> displaying configuration!
>
> Also, what else could be usefully modified?
>
> Chris
>
> ps.
>
>
>>> BTW, see: ~/pgsql/src/backend/commands/explain.c for the new
>>> functions Tom Lane wrote which send explain results to the front
>>> end as if they were from a select statement. Very informative.
>>> Specifically see: begin_text_output(CommandDest dest, char
>>> *title); do_text_output(TextOutputState *tstate, char *aline);
>>> do_text_output_multiline(TextOutputState *tstate, char *text);
>>> end_text_output(TextOutputState *tstate);

I was also thinking about this, but the EXPLAIN approach is only useful
if you never want to select on the output. Another approach might be to
write a function, say show_all(), and then modify gram.y to make:

SHOW ALL;
- equivalent to -
SELECT show_all();

so that you could do:

SELECT show_var() FROM (SELECT show_all()) as s WHERE show_var_name()
LIKE 'wal%';

or something like that.

Joe