Explain

Percona Live Presentation: Improving Performance With Better Indexes

The slides for my Improving Performance With Better Indexes presentation at Percona Live 2015 MySQL Conference and Expo are now available. In this presentation I discuss how to identify, review and analyze SQL statements in order to create better indexes for your queries.

Read more

Recent Presentations Buenos Aires MySQL/NoSQL/Cloud Conference

The first annual Latin America MySQL/NoSQL/Cloud Conference was held in Buenos Aires Argentina from June 26-28. Kudos to Santiago Lertora from Binlogic who had the vision for the conference in his country and made it happen.

Read more

Utilizing multiple indexes per MySQL table join

Historically it was considered that MySQL will generally use only one index per referenced table in a SQL query. In MySQL 5.0 the introduction of merge indexes enabled for certain conditions the possibility to utilize two indexes however this could result in worst performance then creating a better index.

Read more

Extra: Using Index

Many people consider this information in the MySQL Query Execution Plan (QEP) to indicate that the referenced table is using an index. It actually means that ONLY the index is used.

Read more

Optimizing UPDATE and DELETE statements

Updated Nov 2011. Check out my latest book on Optimizing SQL Statements for more information. MySQL 5.6.2 also now provides an EXPLAIN syntax for UPDATE and DELETE statements natively. While most people look at performance optimizations for SELECT statements, UPDATE and DELETE statements are often overlooked.

Read more

10x Performance Improvements in MySQL – A Case Study

The slides for my presentation at FOSDEM 2010 are now available online at slideshare . In this presentation I describe a successful client implementation with the result of 10x performance improvements.

Read more

EXPLAIN – An essential tool for MySQL developers.

Just recently I came across the presentation “Bend SQL to your will with EXPLAIN” by Ligaya Turmelle via the Linked In – MySQL Speakers and Presenters group. Slides available at Slideshare .

Read more

Explain this

The EXPLAIN command is an important tool to review how a SQL query is executed and in this example includes what indexes are used. By adding a covering index I ended up with the following EXPLAIN plan I was unable to explain.

Read more

Understanding Different MySQL Index Implementations

It is important to know and understand that while indexing columns in MySQL will generally improve performance, using the appropriate type of index can make a greater impact on performance.

Read more

A 5.1 QEP nicety – Using join buffer

I was surprised to find yesterday when using MySQL 5.1.26-rc with a client I’m recommending 5.1 to, some information not seen in the EXPLAIN plan before while reviewing SQL Statements.

Read more