ST_3DDistance

Introduction: Return the 3-dimensional minimum cartesian distance between A and B

Format: ST_3DDistance (A: Geometry, B: Geometry)

Return type: Double

Since: v1.3.0

Example:

SELECT ST_3DDistance(ST_GeomFromText("POINT Z (0 0 -5)"),
                     ST_GeomFromText("POINT Z(1  1 -6"))

Output:

1.7320508075688772