ST_ Geohash

Syntax

Parameter

point_geometry

A value of type ST_Point that represents the point geometry for which the geohash is to be calculated. If the specified geometry is NULL or empty, one row with a geohash value of NULL is returned.

depth

A value of type INTEGER in the range 1 - 45 that determines the size of the geohash cell. The following table lists some of the most commonly used depths their corresponding approximate cell sizes.

Geohash Depth	Approximate Cell Size	Description	Examples
45	0.1 km2	Single point or address	GPS-location or house
28	3 km2	Small region	city block
23	100 km2	Medium-sized region	forest or lake
18	3,000 km2	Large region	county or postal code area
13	100,000 km2	Very large (huge) region	state or country

Geohash values of two geometries that are to be compared must be computed using the same depth. An attempt to compare geohash values computed using different depths is invalid.

Restrictions

The specified point geometry must use SRS 4326 (GSE3001N).

• The number of rows returned by this function cannot exceed 10,000 (SQL0443N).
• The specified point geometry must use SRS 4326 (GSE3001N).

Output

A single BIGINT value that is the geohash value of the specified point geometry at depth=45.

A column of type BIGINT with the name GEOHASH containing the geohash value of the specified point geometry at the specified depth.

Example

The following SQL statement returns the geohash, at depth 45, of the point geometry with the coordinates (1,2):

values st_geohash(st_point(1,2))

1
--------------------
-4610318878716198912
1 record(s) selected.

Example

select geohash from table(st_geohash(st_point(1,2), 40))

GEOHASH
--------------------
-4611686018427387904