Subject | Re: [firebird-support] Re: Compound Index |
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Author | Arno Brinkman |
Post date | 2007-05-04T08:40:13Z |
Hi Ivan,
ignoring the base (100 in this case).
Regards,
Arno Brinkman
ABVisie
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
General database developer support:
http://www.databasedevelopmentforum.com
Firebird open source database (based on IB-OE) with many SQL-99 features:
http://www.firebirdsql.org
http://www.firebirdsql.info
Support list for Interbase and Firebird users:
firebird-support@yahoogroups.com
Nederlandse firebird nieuwsgroep:
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> In older FB versions, the clause WHERE COLUMN1 > 100 caused thatIndeed this is improved by Vlad in FB2. We still need to scan the index-entries (thus read index-pages), but are
> even rows with COLUMN1=100 were internally fetched (and discarded).
> Now with FB2 I made a test, and the statistics looks like the index
> is read for values COLUMN1 >= 100, but only rows with COLUMN1 > 100
> are fetched, is it possible ? (The difference of fetches for these two conditions
> seems equal to the number of index pages required for indexing value 100)
> Anyway, ">" now performs much faster thanks to not fetching "=" values.
> Was this improved/fixed in FB2 ? I do not remember
> to see any note in Release notes ...
ignoring the base (100 in this case).
Regards,
Arno Brinkman
ABVisie
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
General database developer support:
http://www.databasedevelopmentforum.com
Firebird open source database (based on IB-OE) with many SQL-99 features:
http://www.firebirdsql.org
http://www.firebirdsql.info
Support list for Interbase and Firebird users:
firebird-support@yahoogroups.com
Nederlandse firebird nieuwsgroep:
news://newsgroups.firebirdsql.info