On 04/16/2014 06:13 PM, Linos wrote:
> I thought that Postgresql would optimize out joins on columns I
> don't ask for when I use the view but it doesn't, this query:
It doesn't, because it would be wrong. It still has to check that the
tables have a matching row (or multiple matching rows).
If you use LEFT JOINs instead, and have a unique index on all the ID
columns, then the planner can do what you expected and leave out the joins.
- Heikki