June 18, 2013

Post: Avoiding auto-increment holes on InnoDB with INSERT IGNORE

November 29, 2011 By 8 Comments

… on MySQL version 5.1.22 or newer? If so, you probably have gaps in your auto-increment columns. A simple INSERT IGNORE… of performance and concurrency. How can I solve this problem for INSERT IGNORE? As I informed you before, it is not documented that INSERT IGNORE…) Insert the same value multiple times. As you will see, the INSERT is ignored and no rows are inserted. The same behaviour as INSERT IGNORE: insert into…

Filed Under: MySQL

Post: Percona XtraDB Cluster: Failure Scenarios with only 2 nodes

July 25, 2012 By 6 Comments

… that there are two options referring to that: – pc.ignore_quorum: Completely ignore quorum calculations. E.g. in case master splits from… 192.168.70.2 -j REJECT and perform an insert, this first insert will take longer: percona1 mysql> insert into percona values (0,’percona1′,’vadim…

Filed Under: MySQL, XtraDB Cluster

Post: Ultimate MySQL variable and status reference list

January 8, 2011 By 4 Comments

…Performance_schema_mutex_classes_lostblogpercona.commanual Performance_schema_mutex_instances_lostblogpercona.commanual Performance_schema_rwlock_classes_lostblogpercona.commanual Performance_schema_rwlock_instances_lostblogpercona.commanual Performance…

Filed Under: Insight for DBAs, MySQL

Post: MySQL Users Conference - Innodb

May 9, 2007 By 6 Comments

…. There are probably similar problems in INSERT IGNORE and ON DUPLICATE KEY UPDATE cases. Now In MySQL 5.1+ it is also possible… READ-COMMITED isolation mode which will start offering more performance benefits in MySQL 5.1 It also should be possible to start… some of them to MySQL 5.0+ Heikki also mentioned there are more things inside Innodb to unleash performance such as multiple…

Filed Under: Events and Announcements Tagged With:

Post: Edge-case behavior of INSERT...ODKU

October 27, 2012 By 6 Comments

…a customer issue wherein they were observing database performance that dropped through the floor (to the …be considered as being defined first. So, MySQL checks our INSERT, sees that the next auto-inc …on username is, for all intents and purposes, ignored. For the customer whose database served as …

Filed Under: Insight for DBAs, Insight for Developers, MySQL

Post: InnoDB Full-text Search in MySQL 5.6: Part 2, The Queries!

March 4, 2013 By 7 Comments

…exactly identical to the same query when performed against InnoDB data, OR that the results…mysql: SET GLOBAL innodb_ft_server_stopword_table=’test/innodb_ft_list2′; Query OK, 0 rows affected (0.00 sec) mysql: INSERT…building the word list, it’s completely ignoring Mr. Smith’s middle initial. To test …

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , , ,

Post: Flexviews - part 3 - improving query performance using materialized views

April 4, 2011 By 20 Comments

… ‘dashboard_customer_sales’, ‘INCREMENTAL’); SET @mvid := LAST_INSERT_ID(); CALL flexviews.add_expr(@mvid,’… ignore this column. It is used to prevent wide innodb primary keys on the MV. mysql… the difference in response time. Refresh method performance comparison For demonstration purposes, I did the…

Filed Under: Insight for DBAs, MySQL

Post: Improved InnoDB fast index creation

November 6, 2011 By 4 Comments

…) mysql> INSERT INTO t(c) VALUES (RAND()); Query OK, 1 row affected (0.00 sec) mysql> INSERT INTO …pool, fast index creation provides even better performance as compared to the default method, …the restore slower; mysqldump –innodb-optimize-keys ignores indexes on AUTO_INCREMENT columns, because …

Filed Under: Benchmarks, Insight for DBAs, MySQL

Post: High-Performance Click Analysis with MySQL

December 22, 2008 By 13 Comments

… your script can figure out which files it can ignore.  What we’re doing here starts to …the hard-to-scale database server for the initial insertion, because you can write CSV files with any … star schemas.  The problem is that MySQL doesn’t tend to perform well on a data warehousing workload. …

Filed Under: Insight for Developers Tagged With: , , , ,

Post: The story of one MySQL Upgrade

October 8, 2010 By 8 Comments

… functionality is used. Happily there are only few INSERT ON DUPLICATE KEY UPDATE query instances, and only …was not the issue for application and could be ignored. So at this point we were sure the … from Percona Server 5.1 back to MySQL 5.0 and performed the same checks again – happily replication …

Filed Under: Insight for DBAs, MySQL Tagged With: ,
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