Re: [HACKERS] Open 7.1 items

At 07:24 26/01/01 +0900, Tatsuo Ishii wrote:
>> Fix for pg_dump of bad system tables
>
>Ok. I have made patches for fixing some of pg_dump problems(see
>attached patches). The patches address the problem with user defined
>functions, operators and aggregates.

These have now been applied with minor modifications.


>However I have not address what Tom Lane said yet(actually I do not
>understand what he says).
>
>> The other flavor of problems that pg_dump
>> has in this area are in doing inner joins across system catalogs ...

This refers to things like:

        SELECT c.relname
        FROM pg_index i, pg_class c
        WHERE i.indrelid = %s
        AND   i.indisprimary
        AND   c.oid = i.indexrelid

ie. where two or more relations are crossed (pg_index and pg_class in this
case). It assumes that the metadata is valid, and will not highlight
missing data in the secondary table. We should be doing outer joins:

        SELECT c.relname
        FROM pg_index i LEFT OUTER JOIN pg_class c on c.oid = i.indexrelid
        WHERE i.indrelid = %s
        AND   i.indisprimary

and checking for nulls using PQgetisnull. I have actually done this for a
couple of SELECTs (including the above one), and marked all the others as
'XXXX: use LOJ'. There are only 2 or 3 more, but they require a little more
thought (an inderstanding) before I change them.

In my view this should be considered a 'work-in-progress' and not hold up
7.1 since the problem has been there for a long time.


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