Re: Our trial to TPC-DS but optimizer made unreasonable plan

On 08/18/2015 04:40 PM, Qingqing Zhou wrote:
> Attached please find the WIP patch and also the ANALYZE results.
> Notes: the patch may not directly apply to head as some network issue
> here so my Linux box can't talk to git server.

So, one of the things we previously mentioned is that currently many
users deliberately use CTEs as an optimization barrier in order to force
the planner.  Given that, we need some kind of option to force the old
behavior; either SQL syntax or a GUC option.  Otherwise this will cause
a bunch of backwards-compatibility breakage.

Ideas?

-- 
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com