Re: [postgis-users] Row estimations

Experiments are here if you would like to try them. https://github.com/postgis/postgis/pull/713 On Wed, Dec 7, 2022 at 2:22 PM Paul Ramsey wrote: > > So, this is rather hard to explain without pictures, but you have to first of > all recognize that the selectivity estimator is an "estimator",

Re: [postgis-users] Row estimations

So, this is rather hard to explain without pictures, but you have to first of all recognize that the selectivity estimator is an "estimator", so you cannot construct synthetic situations and expect things to match exactly. You can just expect them to be worse or better. In particular, things

Re: [postgis-users] PostGIS topology behaviour with polygons

On Wed, Dec 07, 2022 at 11:13:08AM +0100, Douglas Fan wrote: > I am trying to build topology on PostGIS with 4000+ polygons. The input are > not clean, with overlaps and gaps. I have created a procedure to commit > each update statement for each polygon so that I can catch the exception > and

Re: [postgis-users] PostGIS topology behaviour with polygons

[image: test_withgap.png] [image: test_withoutgap.png] On Wed, Dec 7, 2022 at 11:13 AM Douglas Fan wrote: > Hi all, > > Earlier I have asked a question about topology here >

[postgis-users] PostGIS topology behaviour with polygons

Hi all, Earlier I have asked a question about topology here . I still cannot understand the mechanism behind it so I hope that I may get some help here. I am