Re: [HACKERS] CTE inlining

On 05/03/2017 07:33 PM, Alvaro Herrera wrote:
> 1) we switch unmarked CTEs as inlineable by default in pg11.  What seems
> likely to happen for a user that upgrades to pg11 is that 5 out of 10
> CTE-using queries are going to become faster than with pg10, and they
> are going to be happy; 4 out of five are going to see no difference, but
> they didn't have to do anything about it; and the remaining query is
> going to become slower, either indistinguishably so (in which case they
> don't care and they remain happy because of the other improvements) or
> notably so, in which case they can easily figure where to add the
> MATERIALIZED option and regain the original performance.

I am overwhelmingly in favor of this option.

I am in favor of an enable_inlinedcte guc in the same spirit as the
other enable_* gucs, but violently opposed to any "compatibility" guc.

-- 
Vik Fearing                                          +33 6 46 75 15 36
http://2ndQuadrant.fr     PostgreSQL : Expertise, Formation et Support