Re: Join optimization for inheritance tables

Herodotos Herodotou escreveu:
> This patch extends the query optimizer to consider joins between child tables when hierarchies are joined together.
> 
> Short description: when the optimizer considers join paths between two tables with child tables, it only creates join
pathsover two append paths. In this patch we extend the optimizer to consider joins between the child tables from the
twoparent relations, based on the child table constraints. The idea is that only child tables with overlapping
constraintsneed to be joined, and not the entire hierarchies with each other. This optimization can provide significant
benefitsin terms of execution time. A short motivation example as well as the overall algorithm description could be
foundin the attached presentation.
 
> 
I added it to the next commitfest [1].


[1] https://commitfest.postgresql.org/action/commitfest_view?id=3


--  Euler Taveira de Oliveira http://www.timbira.com/