… not to implement clustered indexes which I mentioned in more details later. How does online backup …mentioned the most important criteria. What I can add to this list are 3 things that make … that access PBXT tables may hang waiting for recovery to complete. PBXT seems to have very few configuration…
Post: Statistics of InnoDB tables and indexes available in xtrabackup
September 14, 2009 By 6 Comments
… in InnoDB … you had to calculate it yourself by multiplying size of row (which I should add is harder in the case… to hurt production servers, and the second reason is that running statistic on a stopped database is more accurate than with online (although online is also supported, but you may have inexact results). Let’s see how it works. I have one table…
Post: Intro to OLAP
July 12, 2010 By 10 Comments
… business intelligence tools, particularly OLAP (or online analytical processing) tools using MySQL and …actual dimension table which includes the two different order statuses. Such a dimension would add an…into” and “filtered on” to provide an easy to use interface to the underlying data. Graphical …
Post: Using Flexviews - part one, introduction to materialized views
March 23, 2011 By 3 Comments
… not likely to be very expensive. If the view is large, accessing the table will be considerably cheaper You can add indexes to the… uses the deltas to actually make the changes Finally, the last blog post will describe how to use Flexviews for online schema change, or as an ELT* tool and it will cover how to create the…
Post: When should you store serialized objects in the database?
January 21, 2010 By 47 Comments
… to write back the full blob for 1 change, it is expensive. Another potential pro for this technique is that ALTER TABLE… operations like adding a secondary index on an InnoDB table require the whole table to be rebuilt (now just the index is built… to emulate online index adds. Projects like MMM and Flipper make this even easier. In Friendfeed’s case, they also used the serialization to…
Post: Recovery beyond data restore
August 2, 2008 By 11 Comments
… cases slave should be able to continue after Master is back online. Do you have to wait for master to recover ? This is where… use partial replication, replication to different storage engine, add some tables beyond tables which are being replicated which all has to be accounted for for…
Comment: When should you store serialized objects in the database?
January 21, 2010 By 47 Comments
… in functionality. You can easily run aggregations on the index tables if you like. Or, you can aggregate in process in… using master-slave switching I’ve always been able to emulate online index adds. If you actually run operations for any decent sized… isn’t worth it if you have a lot of tables that you’re often modifying. Sure, this is purportedly fixed…
Comment: Percona Toolkit 2.1 with New Online Schema Change Tool
May 31, 2012 By 10 Comments
… to swing by and leave a thank you for the team here at Percona. Thanks to the online schema tool we were able to add 6 new columns to our most active table on our production system…
Post: MySQL Query Cache
July 27, 2006 By 70 Comments
… be unsuitable for online applications. Limited amount of usable memory – Queries are constantly being invalidated from query cache by table updates, this…+Qcache_hits). As you can see we have to add Qcache_hits to Com_select to get total number of queries as if query… several queries to compose so it is efficient to cache whole objects rather than individual queries. No control on invalidation Table granularity is…
Post: MySQL Upgrade Webinar Questions Followup
June 28, 2012 By 7 Comments
… creating tables a lot faster. You can also use pt-online-schema-change tool for online migration. Q: Should we change ROW replication to… really need all tables changed to Innodb and character set set to utf8? No. MySQL 5.5 continues to support MyISAM tables, so you can… used in production) which adds the difference compared to your production use. If resources allow I prefer to have upgrade testing done in…
