# Geometry Constructors - [BUFFER](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/buffer.md): Returns a geometry representing all points within a given distance of the geometry value. This function calculates a buffer zone around the spatial object. - [CONVEXHULL](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/convexhull.md): Returns a geometry representing the convex hull of the given geometry value. It computes the smallest convex polygon that contains the entire geometry. - [GEOMETRYCOLLECTION](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/geometrycollection.md): Constructs a GeometryCollection value from a list of WKB arguments. This function creates a collection containing multiple geometry objects. - [LINESTRING](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/linestring.md): Constructs a LineString value from a number of Point values. It creates a linear geometry connecting the specified coordinate points. - [MULTILINESTRING](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/multilinestring.md): Constructs a MultiLineString value from a list of WKB LineString arguments. This function creates a collection of multiple line strings. - [MULTIPOINT](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/multipoint.md): Constructs a MultiPoint value from a list of WKB Point arguments. It creates a geometry collection consisting of multiple individual points. - [MULTIPOLYGON](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/multipolygon.md): Constructs a MultiPolygon value from a list of WKB Polygon arguments. This function creates a geometry collection containing multiple polygons. - [POINT](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/point.md): Constructs a Point value using its coordinates. This basic constructor creates a point geometry from given X and Y (and optionally Z/M) values. - [PointOnSurface](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/pointonsurface.md): Returns a Point which is guaranteed to lie on the surface of the given geometry. This is useful for labeling or finding a representative point inside a polygon. - [POLYGON](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/polygon.md): Constructs a Polygon value from a list of WKB LineString arguments. It defines a filled shape using an outer ring and optional inner rings (holes). - [ST\_BUFFER](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/st_buffer.md): Returns a geometry representing all points within a given distance of the geometry. This standard-compliant function creates a buffer zone around the object. - [ST\_CONVEXHULL](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/st_convexhull.md): Returns a geometry representing the convex hull of the given geometry. This standard function computes the smallest convex polygon enclosing the geometry. - [ST\_INTERSECTION](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/st_intersection.md): Returns a geometry representing the point set intersection of two geometries. It outputs the spatial region shared by both input objects. - [ST\_POINTONSURFACE](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/st_pointonsurface.md): Returns a Point guaranteed to lie on the surface of the given geometry. This standard function finds a representative point strictly within the geometry's area. - [ST\_SYMDIFFERENCE](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/st_symdifference.md): Returns a geometry representing the point set symmetric difference of two geometries. It outputs the spatial area present in either geometry but not in both. - [ST\_UNION](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/st_union.md): Returns a geometry representing the point set union of two geometries. This function merges multiple spatial objects into a single geometry. - [ST\_AsGeoJSON](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/geojson-st_asgeojson.md): Generates a GeoJSON object from a given geometry. This function converts internal geometry data into the standard JSON-based format for web mapping. - [ST\_GeomFromGeoJSON](https://mariadb.com/docs/server/reference/sql-statements/geometry-constructors/geometry-constructors/st_geomfromgeojson.md): Parses a GeoJSON string and returns a geometry. 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