SQLite.md

+Mapnik's PluginArchitecture supports the use of different input formats.
+
+One such plugin supports the sqlite ([SQLite](http://en.wikipedia.org/wiki/SQLite)). The plugin works with two types of geometry storage methods - raw OGC WKB and ([Spatialite](http://www.gaia-gis.it/spatialite)) geometries.
+
+You can create a pure SQLite + WKB geometry based sqlite db using ogr like:
+
+    ogr2ogr -f SQLite test.sqlite some.shp
+
+You can create a spatialite enabled db also using ogr:
+
+    ogr2ogr -f SQLite test.sqlite some.shp -dsco SPATIALITE=YES
+
+For more details see: http://www.gdal.org/ogr/drv_sqlite.html
+
+The main difference is that a spatialite enabled db will include a spatial index inside the database. A pure SQLite db will not contain a spatial index, but Mapnik can create one on the fly.
+
+# Parameters
+
+| *parameter*       | *value*  | *description* | *default* |
+|:------------------|----------|---------------|----------:|
+| file                  | string       | sqlite database file path | |
+| base                  | string       | optional base path where to search for the sqlite database file | |
+| table                 | string       | name of the table to fetch, this can be a sub-query | |
+| metadata              | string       | name of the metadata table where the extent and srid of the table are specified | |
+| key_field             | string       | name of the id field of the table | OGC_FID | 
+| geometry_field        | string       | name of the geometry field, in case you have more than one in a single table | the_geom |
+| extent                | string       | maxextent of the geometries | determined by querying the metadata table |
+| row_offset            | integer      | number of rows to skip when querying data | 0 |
+| row_limit             | integer      | max number of rows to return when querying data, 0 means no limit | 0 |
+| wkb_format            | string       | type of WKB in the geometry field blob, this can be "generic",  "spatialite", or "twkb" | not set, determined automatically by testing for generic (WKB) or spatialite content |
+| use_spatial_index     | boolean      | choose wheter to use the spatial index when fetching data | true |
+| multiple_geometries   | boolean      | wheter to use multiple different objects or a single one when dealing with multi-objects (this is mainly related to how the label are used in the map, one label for a multi-polygon or one label for each polygon of a multi-polygon)| false |
+| encoding              | string       | internal file encoding | utf-8 |
+
+# Usage
+
+*Note*: 
+ * Spatial tables read from sqlite by Mapnik _must_ have a cooresponding entry in `geometry_columns`.
+ * Use the `geometry_field` parameter to specify which field to use if you have >1 geometry in the table/query.
+
+## C++
+
+Plugin datasource initialization example code can be found on PluginArchitecture.
+
+A Sqlite datasource may be created as follows:
+
+```cpp
+    {
+        parameters p;
+        p["type"]="sqlite";
+        p["file"]=sqlite_spatial_database_file;
+        p["table"]="bridges";
+        p["geometry_field"]="geom";
+        p["extent"]="2309554.99818767,5024797.73763923,2318414.90507308,5040447.94690007";
+    
+        set_datasource(datasource_cache::instance()->create(p));
+    
+        // Bridges
+        Layer lyr("Bridges");
+        lyr.add_style("bridges"); // in style.xml
+        m.addLayer(lyr);
+    }
+```
+
+## Further References
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