Oracle 5.0 Reference Manual page 1014

+---------------------------+
| Area(GeomFromText(@poly)) |
+---------------------------+
|
+---------------------------+
•
ExteriorRing(poly)
Returns the exterior ring of the
mysql> SET @poly =
-> 'Polygon((0 0,0 3,3 3,3 0,0 0),(1 1,1 2,2 2,2 1,1 1))';
mysql> SELECT AsText(ExteriorRing(GeomFromText(@poly)));
+-------------------------------------------+
| AsText(ExteriorRing(GeomFromText(@poly))) |
+-------------------------------------------+
| LINESTRING(0 0,0 3,3 3,3 0,0 0)
+-------------------------------------------+
•
InteriorRingN(poly,N)
Returns the N-th interior ring for the
beginning with 1.
mysql> SET @poly =
-> 'Polygon((0 0,0 3,3 3,3 0,0 0),(1 1,1 2,2 2,2 1,1 1))';
mysql> SELECT AsText(InteriorRingN(GeomFromText(@poly),1));
+----------------------------------------------+
| AsText(InteriorRingN(GeomFromText(@poly),1)) |
+----------------------------------------------+
| LINESTRING(1 1,1 2,2 2,2 1,1 1)
+----------------------------------------------+
•
NumInteriorRings(poly)
Returns the number of interior rings in the
mysql> SET @poly =
-> 'Polygon((0 0,0 3,3 3,3 0,0 0),(1 1,1 2,2 2,2 1,1 1))';
mysql> SELECT NumInteriorRings(GeomFromText(@poly));
+---------------------------------------+
| NumInteriorRings(GeomFromText(@poly)) |
+---------------------------------------+
|
+---------------------------------------+
12.16.5.2.6.
MultiPolygon
These functions return properties of
•
Area(mpoly)
Returns as a double-precision number the area of the
its spatial reference system.
mysql> SET @mpoly =
-> 'MultiPolygon(((0 0,0 3,3 3,3 0,0 0),(1 1,1 2,2 2,2 1,1 1)))';
mysql> SELECT Area(GeomFromText(@mpoly));
+----------------------------+
| Area(GeomFromText(@mpoly)) |
+----------------------------+
|
+----------------------------+
•
Centroid(mpoly)
Returns the mathematical centroid for the
not guaranteed to be on the MultiPolygon.
Spatial Analysis Functions
4 |
[994]
Polygon
[994]
Polygon
[994]
Functions
MultiPolygon
[993]
8 |
[994]
value as a LineString.
poly
|
value as a LineString. Rings are numbered
poly
|
value poly.
Polygon
1 |
values.
MultiPolygon
value
MultiPolygon
994
value mpoly, as measured in
as a Point. The result is
mpoly