simple (field1,field2) (field2,field1) 1 1 1 1 2 x 1 4 3 x 1 8 4 1 x 2 5 x x 3 6 x x 5 7 x x 6 8 1 x 7 etc select where field2=1 in one case value = 1 could also be the last field1 in the second case the search ends after the third element there may be other elements
-------Messaggio originale------- Da: brucedickin...@wp.pl [firebird-support] Data: 20/07/2015 14.20.37 A: firebird-support@yahoogroups.com Oggetto: Re: Rif: [firebird-support] Re: Is it possible to use only "part" of the index? So, if I change the order of fields in the index I can speed things up. Could someone explain me why it works like it works? What are the internals behind this? [Non-text portions of this message have been removed]