Subject | Re: [firebird-support] Query Performance - correlated subqueries and group by statements |
---|---|
Author | Aage Johansen |
Post date | 2005-04-14T20:26:48Z |
Aaron Abend wrote:
us in helping you.
will use slightly in excess of 64MB for this database. As you open other
databases these will use additional <pagesize>*<buffers>.
8KB may not be optimal for all your databases, and don't use more than
about 8-10000 pages (for one database).
--
Aage J.
>Post table metadata, sql and plan. Also Firebird version. This may help
> I am using Firebird and have found that correlated subqueries and queries
> involving group by statements are unusually slow (compared to MS SQL
> Server).
> I have indexed the tables in what I believe is an appropriate way, based on
> experience in SQL Server and Oracle. Are Firebird index strategies
> significanty different?
us in helping you.
> I also notice that Firebird is not using much memory, which is good, IIf you use a pagesize of 8KB and set the number of page buffers to 8K, Fb
> guess, but at a certain point I'd rather let it eat more memory and run
> faster. It's using only 20 mb of memory right now and going fairly slow on
> these subquery and group by statements.
> In Oracle, for example, I can allocate more database buffers to improve
> performance. Is there a similar concept in Firebird?
will use slightly in excess of 64MB for this database. As you open other
databases these will use additional <pagesize>*<buffers>.
8KB may not be optimal for all your databases, and don't use more than
about 8-10000 pages (for one database).
--
Aage J.