Re: Really dumb planner decision

2009/4/16 Matthew Wakeling <matthew(at)flymine(dot)org>:
> On Thu, 16 Apr 2009, Grzegorz Jaśkiewicz wrote:
>>
>> On Thu, Apr 16, 2009 at 11:37 AM, Matthew Wakeling <matthew(at)flymine(dot)org>
>> wrote:
>>>
>>> I have a query that is executed really badly by Postgres. It is a nine
>>> table
>>> join, where two of the tables are represented in a view. If I remove one
>>> of
>>> the tables from the query, then the query runs very quickly using a
>>> completely different plan.
>>
>> And what happens if you execute that view alone, with WHERE .. just
>> like it would be a part of the whole query? ((id = 1267676))
>
> Really quick, just like the query that works in my email.

What happens if you change join_collapse_limit and from_collapse_limit
to some huge number?

http://www.postgresql.org/docs/current/static/runtime-config-query.html#GUC-FROM-COLLAPSE-LIMIT

...Robert