Re: [HACKERS] "internal error" triggered by EXISTS()
Vadim Mikheev <vadim@krs.ru>
From: Vadim Mikheev <vadim@krs.ru>
To: David Gould <dg@illustra.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@hub.org
Date: 1998-07-15T02:41:09Z
Lists: pgsql-hackers
David Gould wrote: > > > > > I tried the following to find out whether a table has any records > > with field1 < X (for a constant X): > > > > tgl=> SELECT EXISTS(SELECT * FROM table WHERE field1 < X); > > ERROR: internal error: do not know how to transform targetlist > > Should have given a syntax error probably. But you might try: > > select 1 where exists (select...); > > Should be faster if and only if we are doing the existential query > optimization trick (stop on the first qualifying row). We do. Vadim