jkapad@xxxxxxxxxx writes: > ... is quite reasonable.The table has 1.000.000 rows (17.242 pages). From > pg_stat_get_blocks_fetched I can see that there were 102 page requests for > table. So all things seem to work great here! > But if I multiply the size of the table ten-times (10.000.000 rows - 172.414 > pages) and run the same query I get: > ... > which is slower even than a seq scan. Now I get that there were 131.398 page > requests for table in order to retrieve almost 1250 tuples!Can someone explain > why this is happening? All memory parameters are set to default. You probably need to increase work_mem so that the bitmaps don't become lossy ... regards, tom lane
