Re: Analyzing foreign tables & memory problems

Noah Misch <noah@leadboat.com>

From: Noah Misch <noah@leadboat.com>
To: Albe Laurenz <laurenz.albe@wien.gv.at>
Cc: pgsql-hackers@postgresql.org
Date: 2012-05-15T13:08:08Z
Lists: pgsql-hackers
On Mon, May 14, 2012 at 09:21:20AM +0200, Albe Laurenz wrote:
> Noah Misch wrote:
> > Just thinking out loud, we could provide an "extern Datum
> AnalyzeWideValue;"
> > and direct FDW authors to use that particular datum.  It could look
> like a
> > toasted datum of external size WIDTH_THRESHOLD+1 but bear
> va_toastrelid ==
> > InvalidOid.  Then, if future code movement leads us to actually
> examine one of
> > these values, we'll get an early, hard error.
> 
> That would be very convenient indeed.
> 
> Even better would be a function
> extern Datum createAnalyzeWideValue(integer width)
> so that row width calculations could be more accurate.

Yes; good call.