{"id": "spatialite:importing-shapefiles-into-spatialite", "page": "spatialite", "ref": "importing-shapefiles-into-spatialite", "title": "Importing shapefiles into SpatiaLite", "content": "The shapefile format is a common format for distributing geospatial data. You can use the spatialite command-line tool to create a new database table from a shapefile. \n Try it now with the North America shapefile available from the University of North Carolina Global River Database project. Download the file and unzip it (this will create files called narivs.dbf , narivs.prj , narivs.shp and narivs.shx in the current directory), then run the following: \n spatialite rivers-database.db \n SpatiaLite version ..: 4.3.0a Supported Extensions:\n...\nspatialite> .loadshp narivs rivers CP1252 23032\n========\nLoading shapefile at 'narivs' into SQLite table 'rivers'\n...\nInserted 467973 rows into 'rivers' from SHAPEFILE \n This will load the data from the narivs shapefile into a new database table called rivers . \n Exit out of spatialite (using Ctrl+D ) and run Datasette against your new database like this: \n datasette rivers-database.db \\\n --load-extension=/usr/local/lib/mod_spatialite.dylib \n If you browse to http://localhost:8001/rivers-database/rivers you will see the new table... but the Geometry column will contain unreadable binary data (SpatiaLite uses a custom format based on WKB ). \n The easiest way to turn this into semi-readable data is to use the SpatiaLite AsGeoJSON function. Try the following using the SQL query interface at http://localhost:8001/rivers-database : \n select *, AsGeoJSON(Geometry) from rivers limit 10; \n This will give you back an additional column of GeoJSON. You can copy and paste GeoJSON from this column into the debugging tool at geojson.io to visualize it on a map. \n To see a more interesting example, try ordering the records with the longest geometry first. Since there are 467,000 rows in the table you will first need to increase the SQL time limit imposed by Datasette: \n datasette rivers-database.db \\\n --load-extension=/usr/local/lib/mod_spatialite.dylib \\\n --setting sql_time_limit_ms 10000 \n Now try the following query: \n select *, AsGeoJSON(Geometry) from rivers\norder by length(Geometry) desc limit 10;", "breadcrumbs": "[\"SpatiaLite\"]", "references": "[{\"href\": \"https://en.wikipedia.org/wiki/Shapefile\", \"label\": \"shapefile format\"}, {\"href\": \"http://gaia.geosci.unc.edu/rivers/\", \"label\": \"Global River Database\"}, {\"href\": \"https://www.gaia-gis.it/gaia-sins/BLOB-Geometry.html\", \"label\": \"a custom format based on WKB\"}, {\"href\": \"https://geojson.io/\", \"label\": \"geojson.io\"}]"}