> 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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• Re: Recent updates at 1998-07-14 05:02:07 from Bruce Momjian

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• Re: Recent updates at 1998-07-14 13:44:33 from Bruce Momjian

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