I spend a lot of time slicing and dicing OSM and other geodata. Sometimes that is done with custom software but often a database is involved somewhere. Recently that sometimes has been the SQLite/SpatiaLite duo which works great for simple things. But the heavy lifting has to be done with PostgreSQL/PostGIS which has much more “geo functionality” and is much faster when complex queries are used. So here comes the first tip:

Osmium now includes OGR support. OGR is a popular Open Source library for converting different GIS storage formats into each other. It supports PostGIS, Shapefiles, Spatialite, and many other formats. I had started working on OGR integration many weeks ago, but didn’t quite finish it. I have now added the last bit: Support for OGR Multipolygons. This opens up a lot of new possibilities for Osmium users.