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Re: Recent updates

From: "Thomas G(dot) Lockhart" <lockhart(at)alumnus(dot)caltech(dot)edu>
To: Bruce Momjian <maillist(at)candle(dot)pha(dot)pa(dot)us>
Cc: hackers(at)postgreSQL(dot)org
Subject: Re: Recent updates
Date: 1998-07-14 13:38:53
Message-ID: 35AB5F6D.263764EC@apop-server.alumni.caltech.edu (view raw or flat)
Thread:
Lists: pgsql-hackers
> The problem appears to be in the sorting of nulls, which is used by
> UNION ALL:
>         test=> select null order by 1;
>         ERROR:  type id lookup of 0 failed

Hmm. And I've got trouble with the following when I assigned the type
"UNKNOWNOID" to the null fields:

postgres=> select null union select null;
ERROR:  Unable to find an ordering operator '<' for type unknown.
        Use an explicit ordering operator or modify the query.

With "UNION ALL" it works, since no sorting needs to happen:

postgres=> select null union all select null;
?column?
--------


(2 rows)

An additional problem is that the UNION parsing is done recursively, so
the routine which does the type matching does not see a list of all the
clauses all at once.

Any ideas?

                           - Tom

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Next:From: Bruce MomjianDate: 1998-07-14 13:42:47
Subject: Re: [HACKERS] atttypmod now 32 bits, interface change
Previous:From: The Hermit HackerDate: 1998-07-14 13:28:30
Subject: Re: [HACKERS] HPUX Port

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