I have been working with Peter in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a look at and benchmarking optimizer enhancements one by one. So in… new optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
Post: How to Identify Bad Queries in MySQL
January 10, 2011 By 16 Comments
…last three-part definition is where I can‘t be sure that I‘ve got a complete definition. Now, given the definition above, how…in MySQL for years. This is necessary for determining whether a group of queries completed in a cluster. One-second granularity (what you get in standard MySQL…
Post: How to recover deleted rows from an InnoDB Tablespace
February 20, 2012 By 3 Comments
…How can I recover deleted rows? We’re going to follow the same example as in…in our hands the last step is to import it in our database: mysql…Query OK, 3 rows affected (0.01 sec) Records: 3 Deleted: 0 Skipped: 0 Warnings: 0 mysql…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 12 Comments
…time. Both of these views build in about the same about of time: mysql> call flexviews.enable( -> flexviews.get_id(‘demo’,'complete_example2′)); Query…I hope this helps you understand how Flexviews can help you ensure fast response times in…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
…in MySQL. This is very helpful for measurement as otherwise we might not catch some long running connections. Now let’s get…query was executed. Next the “Query_time distribution” section shows how this query times mostly, which you can see majority of the time lies in…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
…Last errno 0 # Users user # Query_time distribution # 1us # 10us # # 100us ################################################################ # 1ms ############# # 10ms ###### # 100ms # # 1s # 10s+ We can see this query takes 2ms to respond in…
Post: MySQL Slow query log in the table
May 31, 2007 By Leave a Comment
…MySQL 5.1 get MySQL slow query log logged in mysql.slow_log table instead of the file as you had in…can do SELECT * FROM (SELECT * FROM slow_log ORDER BY start_time DESC LIMIT 100) l ORDER BY start_time which shows last queries in…
Post: Should we give a MySQL Query Cache a second chance ?
April 10, 2011 By 63 Comments
…in MySQL have very large number of queries doing updates through primary key and use primary key for selects. I believe in such cases we can…in the MySQL Query Cache ? How many hits did we get for this query…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…in size. This will give us some interesting information about how Shard-Query will perform on each database. To do the size comparison, I…mysql> use ontime1; Database changed mysql…in our query response times and throughput. Setting up a cluster using the AMI images You can easily test Shard-Query…
Post: Time for Zero Administration effort at MySQL ?
January 8, 2012 By 4 Comments
…in most cases, in fact I would argue in 95% cases you can get…time however I am happy many more options got exposed over last few years. Majority of options in MySQL…MySQL would use the same sort_buffer_size whenever there is only one query…
