Re: [patch 1/1] WL4092 Remove ndb_use_exact_count - use cache of approximate count instead

On Fri, 2007-10-12 at 07:40 +0200, Jonas Oreland wrote:
> I propose the following (which should not be a huge extra effort)
>
> 1) add a ndb_statistics_check_time (as a mysqld and session variable)

An interesting thing with this is:
- we get row count for free on the get_table_statistics call that the util thread does. So ndb_statistics_check_time would only be relevant for when: a) query cache is disabled or b) is < ndb_cache_check_time.

• This could be confusing. Thoughts?

> 2) create a "struct ndb_statistics_cache" (or similar)
> instead of share->approx_records), so it's easy to add more stuff

could be good...

> 3) make "analyze table A" force an update of the statistics for A

Seeing as the updates are fairly regular, is this really needed?

> 4) have pekka do his index statistics using same machinery

Pekka, does this fit in with your ideas?

-- 
Stewart Smith, Senior Software Engineer
MySQL AB, www.mysql.com
Office: +14082136540 Ext: 6616
VoIP: 6616@sip.us.mysql.com
Mobile: +61 4 3 8844 332

Jumpstart your cluster:
http://www.mysql.com/consulting/packaged/cluster.html


application/pgp-signature attachment: This is a digitally signed message part

Do you need help?

In addition to our free technical library, Pantek provides professional IT services to companies who utilize Open Source software: Learn more about Pantek's Technical Support offerings Place an order for 24/7/365 Technical Support here Learn more about Pantek, who we are, and what we do Chat with a Live Operator Related lists.mysql.com Links announce benchmarks bugs certification cluster commits dotnet gui-tools internals java maxdb myodbc mysql mysqldoc packagers perl plusplus replication win32 Request more information about Pantek