The following table lists each spatial function and provides a short description of each one.

**Table 12.19 Spatial Functions**

Name | Description |
---|---|

`Area()` | Return Polygon or MultiPolygon area |

`AsBinary()` , `AsWKB()` | Convert from internal geometry format to WKB |

`AsText()` , `AsWKT()` | Convert from internal geometry format to WKT |

`Buffer()` | Return geometry of points within given distance from geometry |

`Centroid()` | Return centroid as a point |

`Contains()` | Whether MBR of one geometry contains MBR of another |

`Crosses()` | Whether one geometry crosses another |

`Dimension()` | Dimension of geometry |

`Disjoint()` | Whether MBRs of two geometries are disjoint |

`EndPoint()` | End Point of LineString |

`Envelope()` | Return MBR of geometry |

`Equals()` | Whether MBRs of two geometries are equal |

`ExteriorRing()` | Return exterior ring of Polygon |

`GeomCollFromText()` , `GeometryCollectionFromText()` | Return geometry collection from WKT |

`GeomCollFromWKB()` , `GeometryCollectionFromWKB()` | Return geometry collection from WKB |

`GeometryCollection()` | Construct geometry collection from geometries |

`GeometryN()` | Return N-th geometry from geometry collection |

`GeometryType()` | Return name of geometry type |

`GeomFromText()` , `GeometryFromText()` | Return geometry from WKT |

`GeomFromWKB()` , `GeometryFromWKB()` | Return geometry from WKB |

`GLength()` | Return length of LineString |

`InteriorRingN()` | Return N-th interior ring of Polygon |

`Intersects()` | Whether MBRs of two geometries intersect |

`IsClosed()` | Whether a geometry is closed and simple |

`IsEmpty()` | Placeholder function |

`IsSimple()` | Whether a geometry is simple |

`LineFromText()` , `LineStringFromText()` | Construct LineString from WKT |

`LineFromWKB()` , `LineStringFromWKB()` | Construct LineString from WKB |

`LineString()` | Construct LineString from Point values |

`MBRContains()` | Whether MBR of one geometry contains MBR of another |

`MBRDisjoint()` | Whether MBRs of two geometries are disjoint |

`MBREqual()` | Whether MBRs of two geometries are equal |

`MBRIntersects()` | Whether MBRs of two geometries intersect |

`MBROverlaps()` | Whether MBRs of two geometries overlap |

`MBRTouches()` | Whether MBRs of two geometries touch |

`MBRWithin()` | Whether MBR of one geometry is within MBR of another |

`MLineFromText()` , `MultiLineStringFromText()` | Construct MultiLineString from WKT |

`MLineFromWKB()` , `MultiLineStringFromWKB()` | Construct MultiLineString from WKB |

`MPointFromText()` , `MultiPointFromText()` | Construct MultiPoint from WKT |

`MPointFromWKB()` , `MultiPointFromWKB()` | Construct MultiPoint from WKB |

`MPolyFromText()` , `MultiPolygonFromText()` | Construct MultiPolygon from WKT |

`MPolyFromWKB()` , `MultiPolygonFromWKB()` | Construct MultiPolygon from WKB |

`MultiLineString()` | Contruct MultiLineString from LineString values |

`MultiPoint()` | Construct MultiPoint from Point values |

`MultiPolygon()` | Construct MultiPolygon from Polygon values |

`NumGeometries()` | Return number of geometries in geometry collection |

`NumInteriorRings()` | Return number of interior rings in Polygon |

`NumPoints()` | Return number of points in LineString |

`Overlaps()` | Whether MBRs of two geometries overlap |

`Point()` | Construct Point from coordinates |

`PointFromText()` | Construct Point from WKT |

`PointFromWKB()` | Construct Point from WKB |

`PointN()` | Return N-th point from LineString |

`PolyFromText()` , `PolygonFromText()` | Construct Polygon from WKT |

`PolyFromWKB()` , `PolygonFromWKB()` | Construct Polygon from WKB |

`Polygon()` | Construct Polygon from LineString arguments |

`SRID()` | Return spatial reference system ID for geometry |

`ST_Area()` | Return Polygon or MultiPolygon area |

`ST_AsBinary()` , `ST_AsWKB()` | Convert from internal geometry format to WKB |

`ST_AsText()` , `ST_AsWKT()` | Convert from internal geometry format to WKT |

`ST_Buffer()` | Return geometry of points within given distance from geometry |

`ST_Centroid()` | Return centroid as a point |

`ST_Contains()` | Whether one geometry contains another |

`ST_Crosses()` | Whether one geometry crosses another |

`ST_Difference()` | Return point set difference of two geometries |

`ST_Dimension()` | Dimension of geometry |

`ST_Disjoint()` | Whether one geometry is disjoint from another |

`ST_Distance()` | The distance of one geometry from another |

`ST_EndPoint()` | End Point of LineString |

`ST_Envelope()` | Return MBR of geometry |

`ST_Equals()` | Whether one geometry is equal to another |

`ST_ExteriorRing()` | Return exterior ring of Polygon |

`ST_GeomCollFromText()` , `ST_GeometryCollectionFromText()` , `ST_GeomCollFromTxt()` | Return geometry collection from WKT |

`ST_GeomCollFromWKB()` , `ST_GeometryCollectionFromWKB()` | Return geometry collection from WKB |

`ST_GeometryN()` | Return N-th geometry from geometry collection |

`ST_GeometryType()` | Return name of geometry type |

`ST_GeomFromText()` , `ST_GeometryFromText()` | Return geometry from WKT |

`ST_GeomFromWKB()` , `ST_GeometryFromWKB()` | Return geometry from WKB |

`ST_InteriorRingN()` | Return N-th interior ring of Polygon |

`ST_Intersection()` | Return point set intersection of two geometries |

`ST_Intersects()` | Whether one geometry intersects another |

`ST_IsClosed()` | Whether a geometry is closed and simple |

`ST_IsEmpty()` | Placeholder function |

`ST_IsSimple()` | Whether a geometry is simple |

`ST_LineFromText()` | Construct LineString from WKT |

`ST_LineFromWKB()` , `ST_LineStringFromWKB()` | Construct LineString from WKB |

`ST_NumGeometries()` | Return number of geometries in geometry collection |

`ST_NumInteriorRing()` , `ST_NumInteriorRings()` | Return number of interior rings in Polygon |

`ST_NumPoints()` | Return number of points in LineString |

`ST_Overlaps()` | Whether one geometry overlaps another |

`ST_PointFromText()` | Construct Point from WKT |

`ST_PointFromWKB()` | Construct Point from WKB |

`ST_PointN()` | Return N-th point from LineString |

`ST_PolyFromText()` , `ST_PolygonFromText()` | Construct Polygon from WKT |

`ST_PolyFromWKB()` , `ST_PolygonFromWKB()` | Construct Polygon from WKB |

`ST_SRID()` | Return spatial reference system ID for geometry |

`ST_StartPoint()` | Start Point of LineString |

`ST_SymDifference()` | Return point set symmetric difference of two geometries |

`ST_Touches()` | Whether one geometry touches another |

`ST_Union()` | Return point set union of two geometries |

`ST_Within()` | Whether one geometry is within another |

`ST_X()` | Return X coordinate of Point |

`ST_Y()` | Return Y coordinate of Point |

`StartPoint()` | Start Point of LineString |

`Touches()` | Whether one geometry touches another |

`Within()` | Whether MBR of one geometry is within MBR of another |

`X()` | Return X coordinate of Point |

`Y()` | Return Y coordinate of Point |