Spatial Functions

A spatial function builds spatial objects, analyzes spatial data, and returns metrics from spatial fields. A spatial function can only be used with Spatial data types.

Spatial Functions are consistent with the Open GIS Consortium, Inc. For more information, visit http://portal.opengeospatial.org/files/?artifact_id=829.

Spatial objects in formulas can use these operators:

• + (plus)
• - (minus)
• == (equals)
• != (not equal)

ST_Area

ST_Area(object, units): Returns the area of the spatial object in the specified units (numeric data value).

ST_Boundary

ST_Boundary(object): Returns the boundary of the spatial object (polyline spatial object indicating the boundary of the input polygon).

ST_BoundingRectangle

ST_BoundingRectangle(object, ...): Returns the bounding rectangle of the spatial object (polygon spatial object).

ST_Centroid

ST_Centroid(object): Returns the centroid of the spatial object (point spatial object).

ST_CentroidX

ST_CentroidX(object): Returns the longitude of the centroid of the spatial object (numeric data value).

ST_CentroidY

ST_CentroidY(object): Returns the latitude of the centroid of the spatial object (numeric data value).

ST_Combine

ST_Combine(object1, object2,...): Combines the spatial objects (spatial object).

ST_Contains

ST_Contains(object1,object2): Returns True if object1 contains object2 (Boolean value).

ST_ConvexHull

ST_ConvexHull(object1,...): Returns the convex hull of the spatial objects (spatial object).

ST_CreateLine

ST_CreateLine(point1, point2...): Creates a line by connecting the specified points and lines in a sequence (spatial object).

ST_CreatePoint

ST_CreatePoint(x,y): Returns a spatial object containing the specified longitude and latitude coordinates (spatial object).

ST_CreatePolygon

ST_CreatePolygon(obj1, obj2...): Creates a polygon by connecting the specified points and lines in a sequence (spatial object).

ST_Cut

ST_Cut(object1,object2): Returns the result of cutting object1 from object2 (spatial object).

ST_Dimension

ST_Dimension(object): Returns the dimension of the spatial object. The spatial dimension is the minimum number of coordinates needed to specify every point that makes up the spatial object (numeric data value).

• Point objects return a value of 0.
• Line objects return a value of 1.
• Polygon objects return a value of 2

ST_Distance

ST_Distance(object1, object2, units): Returns the distance from object1 to object2 in the specified units. Supported units are Miles (Mi), Kilometers (KM), Meters, and Feet (numeric data value).

ST_EndPoint

ST_EndPoint(object): Returns the last point of the spatial object (point spatial object).

ST_Intersection

ST_Intersection(object1, object2, ...): Returns the intersection of the specified spatial objects (spatial object).

ST_Intersects

ST_Intersects(object1, object2...): Returns True if the spatial objects intersect (Boolean value).

ST_InverseIntersection

ST_InverseIntersection(object1, object2...): Returns the inverse intersection of the specified spatial objects (spatial object).

ST_Length

ST_Length(object, units): Returns the linear length of the spatial object in the specified units (numeric data value).

ST_MD5

ST_MD5(object): Calculates the MD5 hash of the spatial object.

ST_MaxX

ST_MaxX(object): Returns the maximum longitude of the spatial object (numeric data value).

ST_MaxY

ST_MaxY(object): Returns the maximum latitude of the spatial object (numeric data value).

ST_MinX

ST_MinX(object): Returns the minimum longitude of the spatial object (numeric data value).

ST_MinY

ST_MinY(object): Returns the minimum latitude of the spatial object (numeric data value).

ST_NumParts

ST_NumParts(object): Returns the number of parts in the spatial object (numeric data value).

ST_NumPoints

ST_NumPoints(object): Returns the number of points in the spatial object (numeric data value).

ST_ObjectType

ST_ObjectType(object): Returns the spatial object type as a string value (string data value).

ST_PointN

ST_PointN(object, n): Returns the Nth point in the spatial object (point spatial object).

ST_RandomPoint

ST_RandomPoint(object): Returns a random point within the spatial object (point spatial object).

ST_Relate

ST_Relate(object1,object2,relation): Returns True if the objects satisfy the provided DE-9IM relation (Boolean value).

ST_StartPoint

ST_StartPoint(object): Returns the first point in the spatial object (spatial object).

ST_Touches

ST_Touches(object1, object2): Returns True if object1 touches object2 (Boolean value).

ST_TouchesOrIntersects

ST_TouchesOrIntersects(object1, object2): Returns True if object1 touches or intersects object2 (Boolean value).

ST_Within

ST_Within(object1, object2): Returns True if object1 is contained by object2 (Boolean value).