Re: PATCH: index-only scans with partial indexes

Hi,

On 12/06/2015 11:48 PM, Tomas Vondra wrote:
>    /*
>     * Frequently, there will be no partial indexes, so first check to
>     * make sure there's something useful to do here.
>     */
>    have_partial = false;
>    foreach(lc, rel->indexlist)
>    {
>      IndexOptInfo *index = (IndexOptInfo *) lfirst(lc);
>
>      /*
>       * index rinfos are the same to baseristrict infos for non-partial
>       * indexes
>       */
>      index->indrinfos = rel->baserestrictinfo;
>
>      if (index->indpred == NIL)
>        continue;      /* ignore non-partial indexes */
>
>      if (index->predOK)
>        continue;      /* don't repeat work if already proven OK */
>
>      have_partial = true;
>      break;
>    }

Attached is a v6 of the patch, which is actually the version submitted
by Kyotaro-san on 2015/10/8 rebased to current master and with two
additional changes.

Firstly, I've removed the "break" from the initial foreach loop in
check_partial_indexes(). As explained in the previous message, I believe
this was a bug in the patch.

Secondly, I've tried to improve the comments to explain a bit better
what the code is doing.

regards

--
Tomas Vondra                  http://www.2ndQuadrant.com
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