Re: Indexing dead tuples - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Indexing dead tuples
Date
Msg-id 5483.1125529585@sss.pgh.pa.us
Whole thread Raw
In response to Re: Indexing dead tuples  (Andrew - Supernews <andrew+nonews@supernews.com>)
Responses Re: Indexing dead tuples  (Simon Riggs <simon@2ndquadrant.com>)
List pgsql-hackers
Andrew - Supernews <andrew+nonews@supernews.com> writes:
> On 2005-08-31, Simon Riggs <simon@2ndquadrant.com> wrote:
>> During CREATE INDEX we include all tuples, even if they are already dead
>> when we build an index.
>> 
>> What purpose does this serve?
>> 
>> A pre-existing transaction can't see the index,

> Yes, it can; the catalog is read in SnapshotNow rather than in the query
> snapshot.

In fact, it had better be able to, since once the CREATE INDEX commits,
pre-existing xacts are responsible to insert index entries for anything
they insert into the table.
        regards, tom lane


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