Many thanks Justin & Jeff for your replies.
Presumbly the conditions are partially redundant, so loc_id => user_id
Yes you're right. I had overlooked this.
I've done some further testing and this confirms what you say: if the WHERE
columns are independent, then the Planner makes a reasonable es
On Wed, May 6, 2020 at 12:20 PM Steve Pritchard
wrote:
> Version: Postgres 9.6.3 production system (but also tested on Postgres 12)
>
> For my query the Planner is sometimes choosing an execution plan that uses
> "Bitmap And" (depending on the parameters):
>
> -> Bitmap Heap Scan on observation
On Wed, May 06, 2020 at 05:19:48PM +0100, Steve Pritchard wrote:
> Version: Postgres 9.6.3 production system (but also tested on Postgres 12)
>
> For my query the Planner is sometimes choosing an execution plan that uses
> "Bitmap And" (depending on the parameters):
>
> The Planner then carries t
