![]() However, not all tools use it and other databases might not have (or need) an equivalent. (This datatype is called hstore in PostgreSQL.) hstore is perhaps the most straightforward approach to represent OSM's freeform tagging in PostgreSQL. hstore columns Whether the schema uses a key-value pair datatype for tags. However, if it is not important then it may be better to choose a "lossy" schema, as it is likely to take up less disk space and may be quicker to import. This information is important for editors, and may be of importance to someone doing analysis. Some schemas will retain the full set of OSM data, including versioning, user IDs, changeset information and all tags. Lossless Whether the full set of OSM data is kept. However, if you are doing your own analysis, or are using software which is written to use OSM node/way/relations then you may not need the geometries. If you want to use the database with other bits of software such as a GIS editor then you probably want a schema with these geometries pre-built. Other database schemas may provide enough data to produce the geometries (e.g: nodes, ways, relations and their linkage) but not in a native format. Some database schemas provide native (e.g: PostGIS) geometries, which allows their use in other pieces of software which can read those geometry formats. Geometries Whether the schema has pre-built geometries. However, if you only need a small extract, then re-importing that extract may be a quicker and easier method to keep up-to-date than using the OsmChange diffs. This can be extremely important for keeping world-wide databases up-to-date, as it allows the database to be kept up-to-date without requiring a complete (and space- and time-consuming) full, worldwide re-import. Updatable Whether the schema supports updating with OsmChange format "diffs". OSM uses different database schemas for different applications: ![]() The database schema for the main API database () can be found here: Rails port/Database schema. Legacy XAPI applications can leverage the XAPI Compatibility Layer. The Xapi service allowed OSM data to be downloaded in OSM XML format for a given region of the globe, filtered by tag. It is highly recommended to get familiar with various features via overpass turbo, an interactive Web-based frontend. It’s query language is documented at Overpass QL guide/language reference. It acts as a database backend for various services. location, type of objects, tag properties, proximity, or combinations of them. In contrast to the editing API described in the previous API, the Overpass API is optimized for data consumers that need a few elements within a glimpse or up to roughly 10 million elements in some minutes, both selected by search criteria like e.g. The Overpass API is a read-only API that serves up custom selected parts of the OSM map data. Use other methods for rendering, routing or other purposes.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |