![]() execute ( "INSERT INTO places (id, name, geom) VALUES(null, ?, GeomFromText(?, 4326))", ( "Wales", wkt ), ) conn. json () # Convert to "Well Known Text" format wkt = shape ( geojson ). execute ( "SELECT CreateSpatialIndex('places', 'geom') " ) # Now populate the table from import MultiPolygon from shapely.geometry import shape import requests geojson = requests. execute ( "SELECT AddGeometråolumn('places', 'geom', 4326, 'MULTIPOLYGON', 2) " ) # Add a spatial index against the new column conn. execute ( "create table places (id integer primary key, name text) " ) # Add a MULTIPOLYGON Geometry column conn. execute ( "select InitSpatialMetadata(1)" ) conn. load_extension ( "/usr/local/lib/mod_spatialite.dylib" ) # Create the masic countries table conn. connect ( "places.db" ) # Enable SpatialLite extension conn. 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: Try it now with the North America shapefile available from the University of North Carolina Global River Database project. You can use the spatialite command-line tool to create a new database table from a shapefile. The shapefile format is a common format for distributing geospatial data. This is useful for accelerating within queries, as seen in the Timezones API example. Spatial indexes can be created against polygon columns as well as point columns, in which case they will represent the minimum bounding rectangle of that polygon. rowid in ( SELECT pkid FROM idx_museums_point_geom - left-hand-edge of point > left-hand-edge of bbox (minx) where xmin > : bbox_minx - right-hand-edge of point bottom-edge of bbox (miny) and ymin > : bbox_miny - top-edge of point < top-edge of bbox (maxy) and ymax < : bbox_maxy ) You can inspect its contents using the following query: This takes the form of a SQLite virtual table. In the above example, the resulting index will be called idx_museums_point_geom. They allow you to run efficient bounding box queries using a sub-select, with a similar pattern to that used for Searches using custom SQL. execute ( 'select CreateSpatialIndex("museums", "point_geom") ' ) # If you don't commit your changes will not be persisted: conn. ![]() ![]() execute ( """ UPDATE museums SET point_geom = GeomFromText('POINT('||"longitude"||' '||"latitude"||')',4326) """ ) # Now add a spatial index to that column conn. execute ( "SELECT AddGeometråolumn('museums', 'point_geom', 4326, 'POINT', 2) " ) # Now update that geometry column with the lat/lon points conn. The command in File.txt is as follows: SELECT FROM patients WHERE ID < 3 ORDER BY NAME ASC When connecting to SQLite and opening a database with sqlite3, the following approach forwards the information to the database file. execute ( "select InitSpatialMetadata(1)" ) # Add a geometry column called point_geom to our museums table: conn. This is our third method for executing SQL commands from the file. load_extension ( "/usr/local/lib/mod_spatialite.dylib" ) # Initialize spatial metadata for this database: conn. connect ( "museums.db" ) # Lead the spatialite extension: conn. ![]()
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