Identifying null spatial objects

You can identify null GEOMETRY and GEOGRAPHY objects using the Vertica IS NULL and IS NOT NULL constructs.

This example uses the following table, where the row with id=2 has a null value in the geog field.

=> SELECT id, ST_AsText(geom), ST_AsText(geog) FROM locations
   ORDER BY 1 ASC;
 id |           ST_AsText              |                 ST_AsText
----+----------------------------------+--------------------------------------
  1 | POINT (2 3)                      | POINT (-85 15)
  2 | POINT (4 5)                      |
  3 | POLYGON ((-1 2, 0 3, 1 2, -1 2)) | POLYGON ((-24 12, -15 23, -20 27, -24 12))
  4 | LINESTRING (-1 2, 1 5)           | LINESTRING (-42.74 23.98, -62.19 23.78)
(4 rows)

Identify all the rows that have a null geog value:

=> SELECT id, ST_AsText(geom), (ST_AsText(geog) IS NULL) FROM locations
   ORDER BY 1 ASC;
 id |            ST_AsText             | ?column?
----+----------------------------------+----------
  1 | POINT (2 3)                      | f
  2 | POINT (4 5)                      | t
  3 | POLYGON ((-1 2, 0 3, 1 2, -1 2)) | f
  4 | LINESTRING (-1 2, 1 5)           | f
(4 rows)

Identify the rows where the geog value is not null:

=> SELECT id, ST_AsText(geom), (ST_AsText(geog) IS NOT NULL) FROM locations
   ORDER BY 1 ASC;
 id |            st_astext             | ?column?
----+----------------------------------+----------
  1 | POINT (2 3)                      | t
  2 | POINT (4 5)                      | f
  3 | LINESTRING (-1 2, 1 5)           | t
  4 | POLYGON ((-1 2, 0 3, 1 2, -1 2)) | t
(4 rows)