Download Nameri North A map in DuckDB format
A map built from OpenStreetMap data, ready to download
Customize the map
Open this place's area in the constructor and adjust everything to your needs
Open in constructor →Map passport
What this map contains by default
This is how the map is built as-is — every setting can be changed in the constructor.
.duckdb
About DuckDB
Map of Nameri North A in DuckDB — an export of real OpenStreetMap data for the selected area.
DuckDB is an embedded analytical database its CWI Amsterdam authors call "SQLite for analytics": a single `.duckdb` file, columnar storage, a vectorized engine, and the `ST_*` spatial function set via the spatial extension. Our exporter writes the selected OSM area into a `.duckdb` container where each map layer becomes its own table. To set expectations honestly: geometry is stored as WKT TEXT in a `geom_wkt` column rather than a native GEOMETRY type — to get real geometry you simply call `ST_GeomFromText(geom_wkt)` after `LOAD spatial`. Coordinates stay in WGS84 (EPSG:4326); spatial indexes and Hilbert sorting are not created — those are left to you.
Which layers are in the file
This file for the selected area contains:
- Roads
- Buildings
- Water
- Greenery
- Points of interest
Coordinate systems
WGS 84 (EPSG:4326), selectable in the wizard
Units
Meters (projected in the chosen coordinate system)
| Category | GIS |
| File extension | .duckdb |
| Tier | Open Beta |
How to use DuckDB for Nameri North A
- DuckDB CLI — run duckdb map.duckdb and look around: SHOW TABLES lists the layers, DESCRIBE lists the columns of a particular table.
- Python — import duckdb, then con.execute("INSTALL spatial; LOAD spatial;") and ordinary queries; the result comes straight into pandas.
- Geometry — wrap the column in ST_GeomFromText(geom_wkt), otherwise it stays text: spatial functions do not work with text.
Programs that open DuckDB
FAQ: DuckDB for Nameri North A
Is geometry stored as a native GEOMETRY type?
No. Our exporter writes geometry as WKT text in a `geom_wkt` column. To work with it as real geometry, run `LOAD spatial;` and wrap the column in `ST_GeomFromText(geom_wkt)`. This keeps the file portable — it opens even without the spatial extension.
How does DuckDB differ from SQLite/GeoPackage?
DuckDB is a columnar OLAP database built for analytics (aggregations, joins over millions of rows), while SQLite/GeoPackage are row-oriented OLTP formats. For analytical queries DuckDB is usually much faster; for transactional apps, pick SQLite.
Are spatial indexes created?
No, the exporter does not build an R-tree or Hilbert-sort the data. If you need fast spatial joins, add an index or re-sort the table yourself after opening the file.
What projection is the data in?
Everything is in WGS84 (EPSG:4326) as in source OSM. For a metric projection, apply `ST_Transform(ST_GeomFromText(geom_wkt), 3857)` on your side.
What tables are inside the file?
One table per map layer — roads, buildings, water and the rest — plus the service table _metadata with the export parameters. The list is printed by the SHOW TABLES command.
