On Mon, Dec 09, 2019 at 03:51:39PM -0500, Jeff Janes wrote:
> On Mon, Dec 9, 2019 at 1:00 PM Jeremy Finzel <finzelj@gmail.com> wrote:
>> I have a table with about 7 million records. I had a query in which I
>> needed 2 indexes added, one for a created timestamp field another for an id
>> field; both very high cardinality.
>>
>> First I noticed the query would not use the timestamp index no matter what
>> session config settings I used. I finally created a temp table copy of the
>> table and verified index is used. Then I rebuilt the main table with
>> VACUUM FULL and this caused the index to be used.
>
> Were they built with CONCURRENTLY? Do you have any long-open snapshots?
Something new as of 11 is that btree indexes can be built in parallel,
and before releasing it we found some bugs with covering indexes.
Perhaps we have an issue hidden behind one of these, but hard to be
sure. I have not seen that yet as of v11.
--
Michael