
PostGIS 2.5.0 released - skunkworker
http://postgis.net/2018/09/23/postgis-2.5.0/
======
jakobegger
If you're looking for a quick way to try the new version on your Mac, I made a
new build of Postgres.app that includes PostGIS 2.5.0:
[https://github.com/PostgresApp/PostgresApp/releases](https://github.com/PostgresApp/PostgresApp/releases)

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quaunaut
I've been experimenting with a lot of geo-based projects over the past couple
of years, and something I've been wondering quite a bit lately:

Why is the projection ID(SRID/EPSG) situation so horrendously bad?

As far as I can tell, the only way to take a Shapefile and figure out the
proper SRID number, is to take the .proj4 file and run it through an API like
[http://www.prj2epsg.org/search](http://www.prj2epsg.org/search) (which spent
some number of weeks down earlier this year, and I haven't tried again to see
if the API is back up).

It's funny, because you can't actually take in map data in PostGIS without the
SRID properly set, and yet there's no reliable way to get the number, so
working with multiple projection datasets is just... not possible unless you
manually do the conversions?

Honestly, if I could get the data that the API above has, I'd run the service
myself to at least make it reliable, even though it requires a lookup. But
there should be a better system, somehow.

~~~
sabman
The situation is bad for Shapefiles because people forget to export the prj
file and it can get lost in the process of transformation. I feel your
frustration - it's just a very old format which encodes data into 4 different
files.

This however, has nothing to do with PostGIS. PostGIS will ingest any geo data
you give it. and if you don't know the SRID you can use -1. As for the problem
of Shapefiles there are better alternative formats now like geojson and
spatialite based geodatabases that encode SRID in a single file.

~~~
giancarlostoro
I sort of hope GeoJSON takes off a bit more, it just seems easier to work with
at the very minimum with things like Leaflet. Of course you have Bing which
uses their own objects for their latest rendition of the Bing Maps v8 JS API.
Thankfully using Leaflet we were able to use their imagery instead. Having
dealt with Shapefiles I can say it definitely felt like dealing with something
quite dated, especially compared to how much simpler JSON can be.

~~~
dagw
Everybody is hoping something other than shape files eventually takes off, as
its's universally agreed to be a pretty terrible format. The problem is that
the industry hasn't unified around a single format with GeoJSON, GeoPackage
and to a lesser extend KML all trying to become the next shape file.

As it stands however, everybody and everything can read shape files and that
cannot be said about any other format.

~~~
cwmma
The real annoying thing is that one of the reasons shapefiles are so bad, and
so hard to replace is they fill a bunch of niches in a half assed way and no
sane replacement format is going to replace shapefile in all situations.

Need a standardized way to disseminate data that's super easy to ingest?
GeoJSON and KML work great there, while GeoPackage is going to be not a great
fit for things like APIs plus you can't do a streaming read.

Need a way to edit and work with data locally and maybe send stuff around your
office? Geopackage is going to be a much better fit then GeoJSON or KML.

~~~
dagw
Another 'hidden' feature of shape files that I've seen regularly abused (and
abused myself more than once) is that they use the standard dBASE format to
store their data. Meaning that all kinds of apps that know nothing about shape
files (like Excel or Access) can be used to read and analyse the data stored
within them.

~~~
cwmma
also the encoding of the database is stored in a file that ends in `.cpg`
which I'm pretty sure stands for code page.

Source: I wrote a shapefile parser and generator.

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jcadam
I once worked on a project where we were forced (over the entire engineering
team's objections) to use Oracle Spatial (geospatial add-on for Oracle)
instead of Postgres+PostGIS :( Not nearly as good. Really, expensive as hell
and it doesn't even come close to PostGIS in performance and capability.

Ah, government contracting.

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ingenieroariel
Reading the change log one feature strikes me as very useful for machine
learning projects:

ST_QuantizeCoordinates

With this you should be able to store coordinates with whatever precision they
come with but get back queries that only care about the 'city level' or 'block
level' and can be encoded with an exact number of bytes for a neural net.

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ganzuul
Does PostGIS have any version control or is Geogig the only option for this
still?

~~~
ingenieroariel
I think the answer is still no. Have you had success using geogig? I have been
watching the space and have hopes for solutions like the Dat in Rust rewrite:
[https://datrs.yoshuawuyts.com](https://datrs.yoshuawuyts.com)

~~~
ganzuul
I'm just looking into a match between needs and capabilities at the moment. I
think we want something we can run analysis on in R-spatial, and I'm surprised
this doesn't already exist.

