[postgis-users] Problem with finding intersections with geography types

[Надежда Красовская]

Hi!

I have a database with a column of type "geography" that contains
geographic coordinates of points. I query the database which counts
number of points that are contained in a given polygon.
But I encountered with situation when I get that a point isn't
contained in a polygon but it is contained in another polygon that is
a part of the first one.

Point in database:
POINT(147.88594 70.624908)

I performed three queries:
--select number of points which are contained in polygon
--1
SELECT count(*) from geotest
       where point && 'srid=4326;polygon((146.25 72.3957, 151.875
72.3957, 151.875 70.6126, 146.25 70.6126, 146.25 72.3957))'::geography
   and st_intersects(point, 'srid=4326;polygon((146.25 72.3957,
151.875 72.3957, 151.875 70.6126, 146.25 70.6126, 146.25
72.3957))'::geography);

--select points which are contained in another polygon; the polygon is
contained in polygon from previous select, what is confirmed by third
select
--2
SELECT asewkt(point::geometry) from geotest
       where point && 'srid=4326;polygon((146.25 71.5249, 149.0625
71.5246, 149.0625 70.6126, 146.25 70.6126, 146.25
71.5249))'::geography
   and st_intersects(point, 'srid=4326;polygon((146.25 71.5249,
149.0625 71.5246, 149.0625 70.6126, 146.25 70.6126, 146.25
71.5249))'::geography);

--3
select st_contains('srid=4326;polygon((146.25 72.3957, 151.875
72.3957, 151.875 70.6126, 146.25 70.6126, 146.25 72.3957))'::geometry,
'srid=4326;polygon((146.25 71.5249, 149.0625 71.5246, 149.0625
70.6126, 146.25 70.6126, 146.25 71.5249))'::geometry);

And I got:
 count
-------
     0
(1 row)

                asewkt
--------------------------------------
 SRID=4326;POINT(147.88594 70.624908)
(1 row)

 st_contains
-------------
 t
(1 row)

Is it a bug or may be I perform wrong queries?

I use postgresql 8.4.5 and postgis 1.5.1

Dump of database with this point is in attachment.

-- 
Best Regards, Nadezhda Krasovskaya.
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