ArcMap

ST_Y

Definition

ST_Y takes an ST_Point as an input parameter and returns its y-coordinate. In SQLite, ST_Y can also update the y-coordinate of an ST_Point.

Syntax

Oracle and PostgreSQL

sde.st_y (point1 sde.st_point)

SQLite

double   st_y (point1  geometryblob)
geometry st_y (input_shape geometryblob, new_Yvalue double)

Return type

Double precision

The ST_Y function can be used with SQLite to update the y-coordinate of a point. In that case, a geometryblob is returned.

Example

The y_test table is created with two columns: the gid column, which uniquely identifies the row, and the pt1 point column.

The INSERT statements insert two rows. One is a point without a z-coordinate or measure. The other has both a z-coordinate and a measure.

The SELECT query uses the ST_Y function to return the y-coordinate of each point.

Oracle

CREATE TABLE y_test (
 gid integer unique,
 pt1 sde.st_point
);

INSERT INTO Y_TEST VALUES (
 1,
 sde.st_pointfromtext ('point (10.02 20.02)', 4326)
);

INSERT INTO Y_TEST VALUES (
 2,
 sde.st_pointfromtext ('point zm(10.1 20.01 5.0 7.0)', 4326)
);

SELECT gid, sde.st_y (pt1) "The Y coordinate"
 FROM Y_TEST;

       GID     The Y coordinate

         1          20.02
         2          20.01

PostgreSQL

CREATE TABLE y_test (
 gid integer unique,
 pt1 sde.st_point
);

INSERT INTO y_test VALUES (
 1,
 sde.st_point ('point (10.02 20.02)', 4326)
);

INSERT INTO y_test VALUES (
 2,
 sde.st_point ('point zm(10.1 20.01 5.0 7.0)', 4326)
);

SELECT gid, sde.st_y (pt1) 
 AS "The Y coordinate"
 FROM y_test;

       gid    The Y coordinate

         1          20.02
         2          20.01

SQLite

CREATE TABLE y_test (gid integer);
 
SELECT AddGeometryColumn(
 NULL,
 'y_test',
 'pt1',
 4326,
 'pointzm',
 'xyzm',
 'null'
);

INSERT INTO y_test VALUES (
 1,
 st_point ('point (10.02 20.02)', 4326)
);

INSERT INTO y_test VALUES (
 2,
 st_point ('point zm(10.1 20.01 5.0 7.0)', 4326)
);

SELECT gid, st_y (pt1) 
 AS "The Y coordinate"
 FROM y_test;

gid    The Y coordinate

1          20.02
2          20.01

The ST_Y function can also be used to update the coordinate value of an existing point. In this example, ST_Y is used to update the y-coordinate value of the second point in y_test.

UPDATE y_test
 SET pt1=st_y(
  (SELECT pt1 FROM y_test WHERE gid=2),
  20.1
  )
 WHERE gid=2;

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