Re: Collect frequency statistics for arrays

On Wed, Feb 29, 2012 at 12:39 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Alexander Korotkov <aekorotkov@gmail.com> writes:
>> On Mon, Jan 23, 2012 at 7:58 PM, Noah Misch <noah@leadboat.com> wrote:
>>> I've attached a new version that includes the UINT64_FMT fix, some edits of
>>> your newest comments, and a rerun of pgindent on the new files.  I see no
>>> other issues precluding commit, so I am marking the patch Ready for
>>> Committer.
>>> If I made any of the comments worse, please post another update.
>
>> Changes looks reasonable for me. Thanks!
>
> I am starting to look at this patch now.  I'm wondering exactly why the
> decision was made to continue storing btree-style statistics for arrays,
> in addition to the new stuff.

If I understand you're suggestion, queries of the form

SELECT * FROM rel
WHERE ARRAY[ 1,2,3,4 ] <= x    AND x <=ARRAY[ 1, 2, 3, 1000];

would no longer use an index. Is that correct?

Are you suggesting removing MCV's in lieu of MCE's as well?

-Nathan