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Search Results for: delete using innodb

Lost innodb tables, xfs and binary grep

Before I start a story about the data recovery case I worked on yesterday, here’s a quick tip – having a database backup does not mean you can restore from it. Always verify your backup …


Reasons for run-away main Innodb Tablespace

So you’re running MySQL With innodb_file_per_table option but your ibdata1 file which holds main (or system) tablespace have grown dramatically from its starting 10MB size. What could be the reason of this growth and what …


A quest for the full InnoDB status

When running InnoDB you are able to dig into the engine internals, look at various gauges and counters, see past deadlocks and the list of all open transactions. This is in your reach with one …


Recovering Innodb table Corruption

Assume you’re running MySQL with Innodb tables and you’ve got crappy hardware, driver bug, kernel bug, unlucky power failure or some rare MySQL bug and some pages in Innodb tablespace got corrupted. In such cases …


Efficient Boolean value storage for Innodb Tables

Sometimes you have the task of storing multiple of boolean values (yes/now or something similar) in the table and if you get many columns and many rows you may want to store them as efficient …


Innodb Undelete and Sphinx Support

At Percona we are pleased to announce couple of services which should be helpful to MySQL Community and which are not offered by MySQL, Oracle and other companies I know about. First we now do …


Heikki Tuuri Innodb answers – Part I

Its almost a month since I promised Heikki Tuuri to answer Innodb Questions. Heikki is a busy man so I got answers to only some of the questions but as people still poking me about …


Using VIEW to reduce number of tables used

Many Open Source software solutions use database per user (or set of tables per user) which starts to cause problems if it is used on massive scale (blog hosting, forum hosting etc), resulting of hundreds …


Can Innodb Read-Ahead reduce read performance ?

I ran into pretty interesting behavior today. We needed to dump and reload large database and we had pretty good IO subsystem so we started number of mysqldump processes in parallel. Unlike in other case …


SHOW INNODB STATUS walk through

Many people asked me to publish a walk through SHOW INNODB STATUS output, showing what you can learn from SHOW INNODB STATUS output and how to use this info to improve MySQL Performance. To start …