1. select count(*) from table where indexed_column<10; 2. select * from table where indexed_column<10;
the indexed column is not clustered at all. I saw from the trace that both query runs through index scans on that index and takes the same amount of buffer hits and disk read. However, shouldn't the optimizer notice that the first query only needs to look at the indexes and possibly reduce the amount of buffer/disk visits?
thanks
---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match