Re: Indexing on JSONB field not working

On Sat, Dec 28, 2019 at 02:59:07PM -0500, Zhihong Zhang wrote:
>>
>> Only one of your indexes is over an expression.  The index over a
>> plain column will never have stats, as column stats are stored with
>> the table, not the index.
>>
>
>Oh. That explains it. I tweaked a few server parameters, wonder if that
>made the difference. I changed,
>
>pg_stat_statements.track:    ALL    
>
>track_activity_query_size: 2048
>
>Now we have stats, can anyone see why the index is not used?
>

I don't follow. Neither of these configuration options should affect
which indexes have stats. The expression index should have stats no
matter how these two GUCs are set.

But once again, you're making claims without actually showing us the
data. How do you know we have stats now? Show us pg_stats data and
the explain plans.


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services