Note
Access to this page requires authorization. You can try signing in or changing directories.
Access to this page requires authorization. You can try changing directories.
Applies to: 
Databricks SQL Databricks Runtime 17.1 and above
Important
This feature is in Public Preview.
Note
This feature is not available on Databricks SQL Classic warehouses. To learn more about Databricks SQL warehouses, see SQL warehouse types
Returns the maximum Z coordinate of the input GEOMETRY, or NULL if the geometry is empty or does not have a Z coordinate.
Syntax
st_zmax ( geoExpr )
Arguments
geoExpr: AGEOMETRYvalue.
Returns
A value of type DOUBLE, maximum Z coordinate of the input GEOMETRY.
The function returns NULL if the input is NULL or if the geometry is empty or does not have a Z coordinate.
Examples
-- Returns the maximum Z coordinate of a non-empty geometry with a Z coordinate.
> SELECT st_zmax(st_geomfromtext('LINESTRING Z (10 34 -1,44 57 -2,30 24 -5)'));
-1.0
-- Returns `NULL` for a non-empty geometry without a Z coordinate.
> SELECT st_zmax(st_geomfromtext('LINESTRING(10 34,44 57,30 24)'));
NULL