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I have some experience with PostgreSQL, but not with PostGIS, and for the life of me I can't make my bounding box take the Z axis into account.

I have a points table with XYZ columns. I add another one:

ALTER TABLE foo ADD COLUMN the_geom Geometry(PointZ,4326);

Then I populate the_geom column with my XYZ coordinates:

UPDATE foo
SET the_geom =  ST_SetSRID(ST_MakePoint (x,y,z), 4326)

I confirmed my 3 dimensions with:

SELECT f_geometry_column As col_name, 
    type, 
    srid, 
    coord_dimension As ndims 
FROM geometry_columns

And finally, I can query my data against the bounding box with:

SELECT *
FROM foo
WHERE  the_geom &&  ST_3DMakeBox( ST_MakePoint(0,0,0), ST_MakePoint(6600, 15500, 0)  )

Which should return no rows since in the bounding box the Z axis is 0 and all my Z data is greater than zero, but the query only filters the X and Y axes, not caring about the Z axis.

What am I'm doing wrong, please?

  • As stupid as it looks, just found out about the &&& operator. I've installed the latest postgis (2.1.7) but still no luck... – José Luis Jun 9 '15 at 14:26
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    It seems like something like this: SELECT * from foo where the_geom &&& 'LINESTRING(0 0 0 ,6600 15500 3107.5)'; really works. – José Luis Jun 9 '15 at 16:04
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Try creating an n-d index on your geometry column:

CREATE INDEX foo_gix_nd ON foo USING GIST (the_geom gist_geometry_ops_nd);

Some more information is available here:

http://suite.opengeo.org/opengeo-docs/dataadmin/pgBasics/3d_types.html

  • As a matter of fact I did, found the same link you mentioned. Thanks! Just wished there was an easy way to visually confirm the results...QGIS seems to be 2D only and GRASS GIS is super complicated... – José Luis Jun 17 '15 at 12:07
  • Why do you need to visualize this? your points ahve a z-coord, it is either within the z-bounds in the bbox, or it is not, should be easy enough to tell. – chodgson Jun 17 '15 at 22:25

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