Thread

Re: [BUGS] General Bug Report: Files greater than 1 GB are created while sorting

Bruce Momjian <maillist@candle.pha.pa.us> — 1999-07-09T03:48:37Z

> Bruce Momjian <maillist@candle.pha.pa.us> writes:
> > I have renamed these sort temp tables to pg_sorttemp so they will not be
> > confused with actual temp tables.
> 
> I didn't realize that the names generated for temp tables were so close
> to those generated for temp files.  Changing one or the other does seem
> like a good idea.  But I do not like "pg_sorttemp" because fd.c's
> temporary-file mechanism is used for more things than just sorting.
> Hash joins, for example.  Can we think of a better name?

I am open to other names.  It is really for joining and sorting.
Suggestions?

> 
> Alternatively, how about including the user-given name for a temp table
> into its real name?  That would be helpful for debugging, I'm sure.
> I'm thinking of something like
> 
> 	snprintf(newrelname, NAMEDATALEN, "pg_temp.%d.%u.%s",
> 		 (int) MyProcPid, uniqueId++, userrelname);
> 
> (relying on snprintf to truncate the user name if too long, here).

You can only do the truncation of the user-supplied part, not the actual
numbers.  I guess we could.  I wanted it to be uniform, I guess.


> Note that under ordinary circumstances, the data being processed by a
> sort or hash join will be written into several temp files that each get
> just a fraction of the data; so you would not actually see a problem
> until you got to several-times-2-Gig total data volume.

He already has 1.4 gig sort files.

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