Hi, all! I've been using postgresql for a long time now, but today I had some problem I couldn't solve properly - hope here some more experienced users have some hint's for me. First, I'm using postgresql 7.4.7 on a 2GHz machine having 1.5GByte RAM and I have a table with about 220 columns and 20000 rows - and the first five columns build a primary key (and a unique index). Now my problem: I need really many queries of rows using it's primary key and fetching about five different columns but these are quite slow (about 10 queries per second and as I have some other databases which can have about 300 queries per second I think this is slow): transfer=> explain analyse SELECT * FROM test WHERE test_a=9091150001 AND test_b=1 AND test_c=2 AND test_d=0 AND test_e=0; Index Scan using test_idx on test (cost=0.00..50.27 rows=1 width=1891) (actual time=0.161..0.167 rows=1 loops=1) Index Cond: (test_a = 9091150001::bigint) Filter: ((test_b = 1) AND (test_c = 2) AND (test_d = 0) AND (test_e 0)) So, what to do to speed things up? If I understand correctly this output, the planner uses my index (test_idx is the same as test_pkey created along with the table), but only for the first column. Accidently I can't refactor these tables as they were given to me. Thanks for any hint! Jan
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