ST_MaxY
ST_MaxY takes a geometry as an input parameter and returns its maximum Y coordinate.
If the given geometry is null or is empty, then null is returned.
Syntax
Parameter
- geometry
- A value of one of the seven distinct spatial data types for which the maximum Y coordinate is returned.
Return type
DOUBLE
Examples
Example 1
This example
illustrates the use of the ST_MaxY function. Three polygons are created
and inserted into the SAMPLE_POLYS table.
SET CURRENT PATH = CURRENT PATH, db2gse;
CREATE TABLE sample_polys (id INTEGER, geometry ST_Polygon);
INSERT INTO sample_polys
VALUES (1, ST_Polygon('polygon zm ((110 120 20 3,
110 140 22 3,
120 130 26 4,
110 120 20 3))', 0) );
INSERT INTO sample_polys
VALUES (2, ST_Polygon('polygon zm ((0 0 40 7,
0 4 35 9,
5 4 32 12,
5 0 31 5,
0 0 40 7))', 0) );
INSERT INTO sample_polys
VALUES (3, ST_Polygon('polygon zm ((12 13 10 16,
8 4 10 12,
9 4 12 11,
12 13 10 16))', 0) );
Example 2
This example finds the maximum
Y coordinate of each polygon in SAMPLE_POLYS.
SELECT id, CAST ( ST_MaxY(geometry) AS INTEGER) MAX_Y
FROM sample_polys;
ID MAX_Y
----------- ------------
1 140
2 4
3 13
Example 3
This example finds the maximum
Y coordinate that exists for all polygons in the GEOMETRY column.
SELECT CAST ( MAX ( ST_MaxY(geometry) ) AS INTEGER) OVERALL_MAX_Y
FROM sample_polys;
OVERALL_MAX_Y
--------------
140