Cynic's Blog

Getting pbf files from Geofabrik and uploading them into your own datastore has been discussed in this blog earlier. In this blog, we are gonna see how to update the data, as OSM data changes every day by millions of controbutors worldwide.  It is important to preseve the most recent pbf file in your hard drive, as we'll see in further. The steps to be followed are the following, Download the latest pbf file as per your business requirement. Generate the changes between the last pbf and the earlier version. Apply the change to your PostgreSQL data store. Let's follow this with a concrete example,  Assuming the last pbf we have applied is, india-20220122.osm.pbf dated Jan, 22, 2022. Download the most recent india osm pbf file, india-latest.osm.pbf Generate the change-log in xml format, osmosis-0.48.0/bin/osmosis --read-pbf file="india-latest.osm.pbf" --read-pbf file="india-20220122.osm.pbf" --derive-change --write-xml-change file=inddiff.osc Aplpy the changes...

Opensteetmap is the crowdsourced mapping of the planet and can be accessed at https://opensteetmap.org The map data is freely downloadable and can be hosted locally for any purpose whatsoever under GPL license. Map data is downloadable in multiple archive formats like pbf  (Protocolbuffer Binary Format) and others. OSM's internal data model is represented as shown in the ER diagram above, but when it's imported from the PBF, it has to be efficient, fast and easy to use. Primarily, OSM databases can either be, Snapshot or  Historical Snapshot databases don't contain historical infromation (for instance, how a river changed it's course of the years or how landuse of a forested land changed over the year) whereas, Historical database contains this information. Naturally, historical databases are much more complex and requires more effort. Various parameters on how to judge various data stores are, Updatability Transactibility Concurrent Read/Writability Snapshot/Historical...