Thread: SHOW ALL as a query result

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);
>

Christopher Kings-Lynne writes:

> 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!

Yes, I was going to suggest this myself.  It would be very useful to have
this information available to the JDBC driver so you could query, say, the
default transaction isolation.

-- 
Peter Eisentraut   peter_e@gmx.net

Christopher Kings-Lynne wrote:> Hi All,>> Now that Tom's modified the EXPLAIN output to appear as a query> result,
maybeSHOW 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
beusefully modified?>> Chris>> ps.>>>>> BTW, see: ~/pgsql/src/backend/commands/explain.c for the new>>> functions Tom
Lanewrote which send explain results to the front>>> end as if they were from a select statement. Very informative.>>>
Specificallysee: 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

> -----Original Message-----
> From: Christopher Kings-Lynne [mailto:chriskl@familyhealth.com.au] 
> Sent: 03 April 2002 02:50
> To: Hackers
> Cc: Tom Lane; peter_e@gmx.net
> Subject: SHOW ALL as a query result
> 
> 
> 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!

It certainly would. Of course we've worked around it now though :-(, but
future enhancements.... 

Regards, Dave.

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?

Added to TODO:
       o Allow SHOW to output as a query result, like EXPLAIN

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