Julien Cigar wrote:
On Wed, 2007-11-14 at 11:56 +0000, Richard Huxton wrote:
Julien Cigar wrote:
What I would like is a query that returns all the specimen_id of
this table which have _all_ the given test_bit_id.
[snip]
With the following I got a syntax error:
select specimen_id
from specimen_test_bits
where test_bit_id = all(1,2,3,4);
It's expecting an array here. You'd have to write
= all('{1,2,3,4}')
But that would have the same problem as...
The following works but no rows are returned :
select specimen_id
from specimen_test_bits
where test_bit_id = all(select id from test_bits where id in (1,2,3,4));
It's testing each row individually and of course one row can't match ALL
four values.
What you want to do is count the distinct values. Something like:
SELECT
specimen_id
FROM foo
GROUP BY
specimen_id
HAVING
count(distinct test_bit_id) = 4
;
I don't think it would work, for example if I have:
specimen_id | test_bit_id
------------+------------
100 1
100 3
101 1
101 2
the test_bit_ids are parameters, so with the given test_bit_id 1,3 it
would return specimen_id 101 too, which I don't want ...
Not if you test for what you want too:
...
FROM foo
WHERE test_bit_id = ANY ('{1,3}')
...or...
WHERE test_bit_id IN (1,3)
What I would like is the specimen_id which match _exactly_ the given
test_bit_ids, so it should return only 100 in this example ..
from the documentation ALL() can take a subquery too, not only an ARRAY
(http://www.postgresql.org/docs/8.2/static/functions-subquery.html)
Yes, but that doesn't help with your query - one row can't match ALL
your values.
--
Richard Huxton
Archonet Ltd
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