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Archive for the ‘dat’ Category

Quick (and likely apocryphal) post on versioning and databases

Posted by smathermather on November 15, 2014

This is a quick blog post about technologies that I don’t know well… so please comment if you know better. GeoGig and dat are great tools for addressing versioning in data, so what’s the difference?

Screen shot of GeoGig website

GeoGig is built on Java and meant for any “simple features” geometry (points, lines, polygons).

It’s strength is that it is built from the ground up to handle geometries well, going beyond CRUD functions to specifically address geospatial problems in versioning. Think of it as git for geospatial data.

There’s a hosted version in pre-release from BoundlessGeo called Versio and meant to be the GitHub for geospatial data. You can run your local version from

From the website:

“Users are able to import raw geospatial data (currently from Shapefiles, PostGIS or SpatiaLite) in to (sic) a repository where every change to the data is tracked. These changes can be viewed in a history, reverted to older versions, branched in to sandboxed areas, merged back in, and pushed to remote repositories.”

Ok, so how about dat?

Screen shot of dat website

dat is built on javascript, meant to do streaming data and some other cool features and does CRUD versioning. Think of it as git for data built by web people. Therefore, it “defines an API for reading, writing and syncing datasets”, as opposed to a repository into which one would import data.

“Dat is an open source project that provides a streaming interface between every file format and data storage backend.”

A cursory look indicates it will work for geospatial data, but effectively as blobs, with no special handling for changes within features like GeoGig. But, it does what GeoGig does not, and that is to make datasets automatically syncable.

Like all projects, each has its strengths. Choose your project wisely.

Posted in dat, Database, GeoGig, git, Versio | Tagged: , , , , | 9 Comments »