From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Geoghegan <pg@bowt.ie>
Cc: pgsql-committers <pgsql-committers@lists.postgresql.org>
Subject: Re: pgsql: Add deduplication to nbtree.
Date: Sun, 01 Mar 2020 17:14:03 -0500
Message-ID: <5838.1583100843@sss.pgh.pa.us> (raw)
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Peter Geoghegan <pg@bowt.ie> writes:
> Attached patch shows how this could work. I prefer my original
> approach, but I can see the argument for doing it this way.
This does seem a bit duplicative ... and shouldn't both code paths
include a final "Assert(d == vacposting->ndeletedtids)"? So maybe
we're better off just rejecting the Coverity complaint.
> If we keep my original approach, we should still add a new
> "ItemPointerIsValid(&itup->t_tid)" assertion that covers the plain
> tupe case in a way that mirrors the current "_bt_posting_valid(itup)"
> assert.
Another thing that maybe bears closer scrutiny is the size calculation.
It seems a bit confused as to whether the offset of the posting list
within the tuple, or the total tuple size, or both, needs to be
MAXALIGN'd.
regards, tom lane
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To: pgsql-committers@postgresql.org
Cc: tgl@sss.pgh.pa.us, pg@bowt.ie, pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Add deduplication to nbtree.
In-Reply-To: <5838.1583100843@sss.pgh.pa.us>
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