Windows query weird result

Hi,

had a bit of weird result for a query:
SELECT id FROM spectrum_match WHERE search_id in (788,694,693,685) AND
rescored IS NOT NULL and dynamic_rank = true ORDER BY ID;

returns (among some 127K other lines):
...
32694548
32694860
...

But if I change the query to:
SELECT id FROM spectrum_match WHERE search_id in (788,694,693,685) AND
rescored IS NOT NULL and dynamic_rank = true and id= 32694801;
I get

32694801

which is omitted from the previous result.

The database is running under windows (I know that's bad - but we had
reasons...).
It only became apparent after we made a copy of the database and run it
under Linux (Debian wheezy).
There the first query returned 136k lines and this id was the first
difference.

Does anybody has an idea what is going on?

It's postgresql 9.2.1 running under a windows 2008 R2 server

Lutz

--
Lutz Fischer
lfischer(at)staffmail(dot)ed(dot)ac(dot)uk
+44 131 6517057

The University of Edinburgh is a charitable body, registered in
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