Hi guys. I just wanted to tell you that I've tried every option suggested by Tomas.
Options regarding configuration of the Firebird itself does not change anything. I have not noticed any inrease in performance. However, increasing the size of the page from 4096 to 8192 shortened the index depth and my query is now running 30% faster:) I am observing half less of reads from disk. I guess increasing the size from 8192 to 16384 would gain me even more performance. Thank you for the help :-)
