# Miscellaneous GIS functions

- [ST\_Collect](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_collect.md): Aggregate multiple geometries into a collection. This function creates a MultiPoint, MultiLineString, MultiPolygon, or GeometryCollection from a set of geometry arguments.
- [ST\_GeoHash](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_geohash.md): Generate a Geohash string from a point or coordinates. This function encodes spatial locations into short, alphanumeric strings for efficient indexing and proximity searches.
- [ST\_IsValid](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_isvalid.md): Check if a geometry is valid. This function returns 1 if the geometry complies with OGC specifications (e.g., no self-intersections), 0 otherwise.
- [ST\_LatFromGeoHash](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_latfromgeohash.md): Decode a Geohash to retrieve the latitude. This function returns the latitude coordinate (Y-axis) from a given Geohash string.
- [ST\_LongFromGeoHash](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_longfromgeohash.md): Decode a Geohash to retrieve the longitude. This function returns the longitude coordinate (X-axis) from a given Geohash string.
- [ST\_PointFromGeoHash](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_pointfromgeohash.md): Create a Point geometry from a Geohash. This function decodes a Geohash string into a Point object representing the location's center.
- [ST\_Simplify](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_simplify.md): Simplify a geometry using the Douglas-Peucker algorithm. This function reduces the number of vertices in a geometry while preserving its general shape, useful for rendering maps.
- [ST\_Validate](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/miscellaneous-gis-functions/st_validate.md): Validate and optionally return a geometry. This function checks if a geometry is valid according to OGC rules; it returns the geometry if valid, or NULL if not.


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