Emergency

Search Results for: index size information_schema

MySQL compression: Compressed and Uncompressed data size

MySQL has information_schema.tables that contain information such as “data_length” or “avg_row_length.” Documentation on this table however is quite poor, making an assumption that those fields are self explanatory – they are not when it comes …

Read More
 

Quickly finding unused indexes (and estimating their size)

I had a customer recently who needed to reduce their database size on disk quickly without a lot of messy schema redesign and application recoding.  They didn’t want to drop any actual data, and their …

Read More
 

Find unused indexes

I wrote one week ago about how to find duplicate indexes. This time we’ll learn how to find unused indexes to continue improving our schema and the overall performance. There are different possibilites and we’ll …

Read More
 

Innodb vs MySQL index counts

I had a customer recently who a few strange errors in their mysqld.err log:

This customer was running Percona Server 5.1 and they got this error on two tables during a maintenance window when …

Read More
 

Getting History of Table Sizes in MySQL

One data point which is very helpful but surprisingly few people have is the history of the table sizes. Projection of data growth is very important component for capacity planning and simply watching the growth …

Read More
 

InnoDB TABLE/INDEX stats

In Released and new coming features I did not mentioned two additional INFORMATION_SCHEMA tables available in XtraDB: It is INNODB_TABLE_STATS INNODB_INDEX_STATS These table show statistics about InnoDB tables ( taken from InnoDB data dictionary). INNODB_TABLE_STATS …

Read More
 

Researching your MySQL table sizes

I posted a simple INFORMATION_SCHEMA query to find largest tables last month and it got a good response. Today I needed little modifications to that query to look into few more aspects of data sizes …

Read More
 

Advanced Query Tuning in MySQL 5.6 and MySQL 5.7 Webinar: Q&A

Thank you for attending my July 22 webinar titled “Advanced Query Tuning in MySQL 5.6 and 5.7” (my slides and a replay available here). As promised here is the list of questions and my answers …

Read More
 

Percona XtraDB Cluster 5.6.24-25.11 is now available

Percona is glad to announce the new release of Percona XtraDB Cluster 5.6 on June 3rd 2015. Binaries are available from downloads area or from our software repositories. Based on Percona Server 5.6.24-72.2 including all …

Read More