chore: import upstream snapshot with attribution

docs/tutorials/spatial-sql.md

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+# Spatial SQL
+
+The [SQL Workspace](../user-guide/sql-workspace.md) lets you analyze data with DuckDB Spatial SQL and add the results to the map. It runs on DuckDB-WASM, so it works in the browser as well as the desktop app. Open it from **Processing → SQL Workspace**.
+
+## 1. Query a loaded layer
+
+Every loaded vector layer is a queryable table. Load the sample countries layer (see [Your First Map](first-map.md)), then run:
+
+```sql
+SELECT NAME, CONTINENT, GDP_MD_EST
+FROM countries
+ORDER BY GDP_MD_EST DESC
+LIMIT 10;
+```
+
+Click **Run** to see the ten countries with the highest estimated GDP.
+
+!!! note "Sample dataset columns"
+    `NAME`, `CONTINENT`, `POP_EST`, and `GDP_MD_EST` are Natural Earth field names in the sample `countries.parquet`, whose geometry column is `geom`. A different dataset will have its own column names. To discover them, run `DESCRIBE SELECT * FROM 'your-file-url'` first.
+
+## 2. Query a remote file directly
+
+You do not have to load a file first. The Workspace detects a bare URL in a `FROM` clause and wraps it in the right reader automatically, then streams the file over HTTP range requests so you do not download it in full. This bare-URL shorthand is a SQL Workspace convenience; in the standard DuckDB CLI you would write `read_parquet('https://...')` explicitly.
+
+```sql
+SELECT COUNT(*) AS n
+FROM https://data.source.coop/giswqs/opengeos/countries.parquet;
+```
+
+## 3. Use spatial functions
+
+The spatial extension is loaded, so `ST_*` functions are available. For example, compute area and keep the `geom` column so the result can be mapped:
+
+```sql
+-- area is in square degrees because the data is in EPSG:4326;
+-- the ranking is valid, but use ST_Area_Spheroid(geom) / 1e6 for km2.
+SELECT NAME, ST_Area(geom) AS area, geom
+FROM https://data.source.coop/giswqs/opengeos/countries.parquet
+WHERE CONTINENT = 'Africa'
+ORDER BY area DESC;
+```
+
+## 4. Add the result to the map
+
+When a query returns a geometry column, use **add to map** to create a new layer from the result, optionally naming it. The result layer supports [identify, selection, and the attribute table](../user-guide/attribute-table.md) like any vector layer, and you can add several result layers at once.
+
+## 5. Export
+
+Export the query result as **CSV** or **GeoParquet** straight from the workspace. See [SQL Workspace](../user-guide/sql-workspace.md).
+
+!!! tip "Sample queries and history"
+    Use the **Sample queries** menus to start from a working query, and the **history** to rerun a previous one.
+
+## Next steps
+
+- Do equivalent geometry operations with the menu-driven [Vector Analysis](vector-analysis.md) tools.
+- Convert results to cloud-native formats in [Cloud-Native Data](cloud-native-data.md).