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PostGIS – Spatial and Geographic Objects for PostgreSQL

postgis.net

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Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#43
post #16

I've been using PostGIS a bit for a toy project with Elite: Dangerous star system data. It's been a hoot, but I do worry that I'm going to start having trouble optimizing my queries. Finding all the systems within say 20 Ly of our sun can take upwards of a few seconds, and I've already added a GIST index on the positions. I also find it a bit strange how 3D feels kinda tacked on, but it makes sense when you realize m…

Is it possible you haven't added the bounding box for your geometries? The GIST index will use your bounding box to optimise the queries, but only if it finds one. Also make sure your query is actually using the index.

assuming you're using the postgis spatial data types (and not the postgres ones) it'll take care of that automatically.

Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#44

I've been using PostGIS a bit for a toy project with Elite: Dangerous star system data. It's been a hoot, but I do worry that I'm going to start having trouble optimizing my queries. Finding all the systems within say 20 Ly of our sun can take upwards of a few seconds, and I've already added a GIST index on the positions. I also find it a bit strange how 3D feels kinda tacked on, but it makes sense when you realize m…

there is a specific command you need to use to create a 3d index

CREATE INDEX [indexname] ON [tablename] USING GIST ([geometryfield] gist_geometry_ops_nd);

by default postgis just creates 2d ones

Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#45

A couple of excellent GIS related links I would recommend to anyone interested in this area. Talks and writing by PostGIS co-creator Paul Ramsey (who is incredible): http://blog.cleverelephant.ca/writings The mapscaping podcast - a lot of intros to the complex and overlapping worlds of GIS: https://mapscaping.com/blogs/the-mapscaping-podcast

Talks by Paul Ramsey are usually a highlight of any GIS conference.

Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#46

A couple of excellent GIS related links I would recommend to anyone interested in this area. Talks and writing by PostGIS co-creator Paul Ramsey (who is incredible): http://blog.cleverelephant.ca/writings The mapscaping podcast - a lot of intros to the complex and overlapping worlds of GIS: https://mapscaping.com/blogs/the-mapscaping-podcast

Paul also has quite a few posts on the Crunchy Data blog as well - https://blog.crunchydata.com/blog/author/paul-ramsey

Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#47
post #33

PostGIS is loads of fun with sports data. Being able to find similar passages of play just using ST_MakeLine and ST_FrechetDistance feels like magic when you first do it in all of five lines of code. Spatial tools are a bit like logic programming in that they’re very slightly esoteric. But once you know they’re the right hammer for some nails, they’ll save you lots of time and effort over your life, and let you expre…

This sounds really interesting. Was thinking it would be cool to build a hobby project in this space, but wasn't sure how to get started.

Do you have any recommended sources for sample datasets to play around with?

Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#48
What would be a good front end framework to use with PostGIS with capable rendering of GiS artifacts to make a compete desktop GIS application?

The only viable open source route I am seeing is through some kind of QGIS extensions. Is there something better for that purpose?

Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#49

I've been using PostGIS a bit for a toy project with Elite: Dangerous star system data. It's been a hoot, but I do worry that I'm going to start having trouble optimizing my queries. Finding all the systems within say 20 Ly of our sun can take upwards of a few seconds, and I've already added a GIST index on the positions. I also find it a bit strange how 3D feels kinda tacked on, but it makes sense when you realize m…

What kind of front end do you use. Usually the spatial db is only a part of the solution, and the GIS information needs to displayed and functionality for interaction with maps and objects needs to provided. What framework would pair well with PostGis in the open source world?

Re: PostGIS – Spatial and Geographic Objects for PostgreSQL

#50
post #8

PostGIS is one of those rare examples of highly specialised software that is both OSS and best-in-class. Usually OSS is relegated for highly commoditized software but GIS is anything but even after all these years. I can't really think of many others? Maybe OptaPlanner would be another candidate.

Yes, among off-the-shelf GIS databases, PostGIS is generally as good or better than anything else on the market. More capable systems exist, particularly in terms of scale and performance, but those are all bespoke.
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