On 10/12/2017 12:24:11 AM, "Luigi Siciliano luigi...@tiscalinet.it [firebird-support]" <firebird-support@yahoogroups.com> wrote:
>Hallo, > >Il 11/10/2017 20.38, setysvar setys...@gmail.com [firebird-support] ha >scritto: >>I think this should give the same result as your query, whether or not >>it is any quicker, I simply do not know (but I would love to hear if >>it >>made any difference). > >Your query is to slow, flamerobin tells 4.360s. :( >>PLAN (PNC2 NATURAL) >> >>seems to be your problem (PNC on the other hand, seems OK). >> >>Hence, if PARITA and/or SCADENZA are selective, I would recommend that >>you create an index for either or both of these fields. That way, I >>would assume your original query to become a lot quicker. >Ok, I create an index for PARTITA and SCADENZA fields for PNC and Your >query speed up, Flamerobin now tells 0.060s :) > >And, my query, now, flamerobin tells 0.045s :)) > >The secondary index are automatically maintained by server, is it right >to do a periodically manually maintenance for it's? > It would be interesting to compare the plans for both your original query syntax and Set's suggestion - see where the difference is. As for index maintenance, see http://www.firebirdfaq.org/faq167/ With a significant amount of deletes database maintenance becomes more important. Static tables, or tables that generally just grow, don't experience much fragmentation. -- Daniel
