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st_zmin function

Applies to: check marked yes Databricks Runtime 17.1 and above

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Returns the minimum Z coordinate of the input GEOMETRY, or NULL if the geometry is empty or does not have a Z coordinate.

Syntax

st_zmin ( geoExpr )

Arguments

  • geoExpr: A GEOMETRY value.

Returns

A value of type DOUBLE, minimum 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

SQL
-- Returns the minimum Z coordinate of a non-empty geometry with a Z coordinate.
> SELECT st_zmin(st_geomfromtext('LINESTRING Z (10 34 -1,44 57 -2,30 24 -5)'));
-5.0
-- Returns `NULL` for a non-empty geometry without a Z coordinate.
> SELECT st_zmin(st_geomfromtext('LINESTRING(10 34,44 57,30 24)'));
NULL