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Search Results for: mysql innodb count trigger

How to monitor ALTER TABLE progress in MySQL

While working on a recent support issue as a Percona Support Engineer,  I got one question from a customer asking how to monitor ALTER TABLE progress. Actually, for MySQL 5.5 and prior versions, it’s quite difficult to ALTER the …


How to reclaim space in InnoDB when innodb_file_per_table is ON

When innodb_file_per_table is OFF and all data is going to be stored in ibdata files. If you drop some tables of delete some data then there is no any other way to reclaim that unused …


Schema changes – what’s new in MySQL 5.6?

Among many of the improvements you can enjoy in MySQL 5.6, there is one that addresses a huge operational problem that most DBAs and System Administrators encounter in their life: schema changes. While it is …


Percona XtraDB Cluster 5.5.30-23.7.4 for MySQL now available

Percona is glad to announce the release of Percona XtraDB Cluster 5.5.30-23.7.4 for MySQL on April 17, 2013. Binaries are available from the downloads area or from our software repositories. New Features: Percona XtraDB Cluster …


MySQL Workshops: Chicago & London this April

Percona will be in Chicago and London the week of April 8th delivering two 2-day MySQL workshops. For our MPB readers, we are offering a 15% discount. Just use MPB15A when purchasing your tickets to …


MySQL optimizer: ANALYZE TABLE and Waiting for table flush

The MySQL optimizer makes the decision of what execution plan to use based on the information provided by the storage engines. That information is not accurate in some engines like InnoDB and they are based …


Should we give a MySQL Query Cache a second chance ?

Over last few years I’ve been suggesting more people to disable Query Cache than to enable it. It can cause contention problems as well as stalls and due to coarse invalidation is not as efficient …


Ultimate MySQL variable and status reference list

I am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to look up blog posts on variables, or look for content in the …


How much memory can MySQL use in the worst case?

I vaguely recall a couple of blog posts recently asking something like “what’s the formula to compute mysqld’s worst-case maximum memory usage?” Various formulas are in wide use, but none of them is fully correct. …