Re: "Re-indexing" Informix

Will be nice if, some day,  IBM create the "index repack" (sysadmin API) to regroup the index extents without need read all table. --- Em seg, 27/9/10, Fernando Nunes <domusonline@gmail.com> escreveu: De: Fernando Nunes <domusonline@gmail.com> Assunto: Re: "Re-indexing" Informix Para: informix-list@iiug.org Data: Segunda-feira, 27 de Setembro de 2010, 12:55 On Mon, Sep 27, 2010 at 3:47 PM, red_valsen <red_valsen@yahoo.com> wrote: Here's what happened after indexes were dropped and recreated:  The number of extents used by individual indexes was substantially reduced.  Greatest number prior was 176; afterwards, 9.  I'm somewhat surprised, yet can't see that this would have anything but a positive effect on performance, even if to a minor degree.  I'll have to do a little digging to explain the change. This is perfectly normal. The B-Tree scanner will not reduce index extents. So don't be surprised. What you should check it the number of extents on your tables. The index number of extents should somewhat reflect the table number of extents. And 176 is too high specially if your pagesize is 2K. Regardind performance, yes, if you were able to measure any difference it would be an improvement. But again, this would only be noticeable if you did frequent and very large index range scans. Regards. -- Fernando Nunes Portugal http://informix-technology.blogspot.com My email works... but I don't check it frequently... -----Anexo incorporado----- _______________________________________________ Informix-list mailing list Informix-list@iiug.org http://www.iiug.org/mailman/listinfo/informix-list