Mario Ivankovits <mario@xxxxxxxxx> writes: > After populating the table with 8920 records and "analyze" the scenario > gets even worser: > select * from tt where seckey = 1; > Seq Scan on tt (cost=0.00..168.50 rows=1669 width=12) (actual > time=0.000..15.000 rows=1784 loops=1) > Filter: (seckey = 1) > Total runtime: 31.000 ms > Now also this simple query uses a "Seq Scan". Which is exactly what it *should* do, considering that it is selecting 1784 out of 8920 records. Indexscans only win for small selectivities --- the rule of thumb is that retrieving more than about 1% of the records should use a seqscan. regards, tom lane
