st_dimension function

Applies to: Databricks Runtime 17.1 and above

Returns the topological dimension of the 2D projection of the GEOMETRY.

Syntax

st_dimension ( geoExpr )

Arguments

• geoExpr: A GEOMETRY value.

Returns

Returns the topological dimension of the 2D projection of the input GEOMETRY. The expression returns:

• 0, if the input GEOMETRY is a point or a multipoint.
• 1, if the input GEOMETRY is a linestring or a multilinestring.
• 2, if the input GEOMETRY is a polygon or a multipolygon.
• 0, if the input is an empty GEOMETRY collection.
• The maximum dimension of elements of the collection, if the input is a non-empty geometry collection.

Examples

> SELECT st_dimension(st_geomfromtext('MULTIPOINT(EMPTY,-1 0,EMPTY)'))
  0

> SELECT st_dimension(st_geomfromtext('LINESTRING(-1 0,0 -1,1 0,0 1,-1 0)'))
  1

> SELECT st_dimension(st_geomfromtext('MULTIPOLYGON(EMPTY,((-1 0,0 -1,1 0,0 1,-1 0)))'))
  2

> SELECT st_dimension(st_geomfromtext('GEOMETRYCOLLECTION EMPTY'))
  0

Related functions

• st_geometrytype function
• st_ndims function