Imposm¶

Imposm is an importer for OpenStreetMap data. It reads PBF files and imports the data into PostgreSQL/PostGIS databases. It is designed to create databases that are optimized for rendering/tile/map-services.

It is developed and supported by Omniscale and is released as open source under the Apache Software License 2.0. Imposm >=3 is a rewrite of Imposm 2 with even better performance and support for (minutely) diff updates.

Features¶

Custom database schemas: It creates separate tables for different feature types. This allows easier styling and better performance for rendering in tile or WMS services.
Multiple CPU/core support: Imposm is parallel from the ground up. It distributes parsing and processing to multiple CPUs/cores.
Unify values: For example, the boolean values 1, on, true and yes all become TRUE.
Filter by tags and values: It only imports data you are going to render/use.
Efficient nodes cache: It is necessary to store all nodes to build ways and relations. Imposm uses a file-based key-value database to cache this data. This reduces the memory usage.
Generalized tables: It can automatically create tables with lower spatial resolutions, perfect for rendering large road networks in low resolutions for example.
Limit to polygons: It can limit imported geometries to polygons from GeoJSON.
hstore support: Don’t know which tags you will be needing? Store all tags in an hstore column.