… join category using(category_id) where name=’Music’; and let’s say you want to change the left joins to inner joins and use capital letters for reserved SQL words. Instead of manually editing the statement… of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql> select count…
Post: Database access Optimization in Web Applications.
September 12, 2006 By 10 Comments
… this information delivered from the database most efficient way. Investigate how dynamic is this information If information rarely changes or is static it… retrieved from the database matches information you display Way to often much more information is retrieved from the database than used to generate the page… killer queries are GROUP BY Queries and Sort Queries – SELECT name,descr FROM titles ORDER BY rank DESC LIMIT 10 – If…
Post: The relationship between Innodb Log checkpointing and dirty Buffer pool pages
February 17, 2012 By 10 Comments
… to rebuild the last consistent picture of the database. Recovery uses the transaction log by redoing (hence the name ‘redo log’) the page operations in the log that… the changes into a log, it will be faster to do on the fly as transactions come in than trying to randomly write the changes…
Comment: Are PHP persistent connections evil ?
December 17, 2010 By 32 Comments
… probably use the same username, password and database for all of the servers, just changing the host name, but you’re not forced to use the same ones): // ‘myHost1′, ‘username’ => ‘myUsername1′, ‘password’ => ‘myPassword1′, ‘database…
Comment: Are PHP persistent connections evil ?
December 17, 2010 By 32 Comments
… probably use the same username, password and database for all of the servers, just changing the host name, but you’re not forced to use the same ones): ‘myHost1′, ‘username’ => ‘myUsername1′, ‘password’ => ‘myPassword1′, ‘database…
Post: Filling the tmp partition with persistent connections
August 6, 2012 By 14 Comments
…The application starts to load data into the database with “LOAD DATA INFILE”. After some minutes the…the temporary data it will create a on-disk cache on the tmp partition with the name ML*. Here is the problem. Until the…Change the session value of binlog_format to STATEMENT just before the …
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 20 Comments
… named after the way in which the contents of the view are updated. The two methods are complete refresh and incremental refresh. Â The …’ since changes to the database may have happened since the backup was taken. Replaying the binary logs brings the database up-to-date by replaying the changes. …
Post: Updated msl (microslow) patch, installation walk-through!
April 20, 2008 By 17 Comments
… through the installation and configuration because things changed along the way. Installation In order to use the patch first you will need to build the database… the replication thread. Can be changed at run time with both SET SESSION and SET GLOBAL. log_slow_verbosity=name Choose how verbose the…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…the database. The first step is to find out what MySQL instances are on the…The changes Percona’s performance audits typically suggest can be really significant, and can completely change the…
Post: Find and remove duplicate indexes
June 20, 2012 By 9 Comments
…on (name) the execution plan is Using intersect(name,PRIMARY); Using where and with an index on (name,id) the execution plan changes … `name` (`name`,`i`), KEY `name_2` (`name`), KEY `name_3` (`name`), KEY `name_4` (`name`,`age`), KEY `age` (`age`,`name`,`i`) I run the tool on the ‘test’ database: …
