…a lot of memory for table cache, especially if you’re using large blobs…exist for duration of query execution so it is usually easy to catch them. There are also explicit MEMORY tables you can create…tables application can create it does not really allows to restrict memory usage. For Permanent tables…
Comment: InnoDB's gap locks
April 13, 2012 By 14 Comments
…READ transaction isolation level. mysql> show create table t\G *************************** 1. row *************************** Table: t Create Table: CREATE TABLE `t` ( `i` int(11) DEFAULT NULL, …, because it doesn’t exist anymore. I hope this example clarify your questions, if not, feel free to ask …
Post: Best kept MySQLDump Secret
March 23, 2012 By 11 Comments
… DROP TABLE IF EXISTS `C`; /*!40101 SET @saved_cs_client = @@character_set_client */; /*!40101 SET character_set_client = utf8 */; CREATE TABLE `C` ( `t` char(255) NOT NULL, `i` int(11) NOT NULL ) ENGINE=InnoDB DEFAULT CHARSET=latin1…
Post: How to diagnose errors in the MySQL error log
March 26, 2012 By 4 Comments
…:56:45 [ERROR] /usr/sbin/mysqld: Incorrect key file for table ‘/tmp/#sql_21b2_0.MYI’; try to repair it 120326…’s the key to understanding what really happened. MySQL created a temporary table, using the MyISAM storage engine, and when the disk… it exists!” In cases such as these you need to dig more deeply. The error code is not wrong, I promise you. If…
Post: Announcement of Percona XtraDB Cluster 5.5.20 GA release
April 3, 2012 By 10 Comments
…everyone. You can convert your existing MySQL replication setup into a…Percona XtraDB Cluster works with databases created in MySQL / Percona Server Application …. Schema change does not block operations against table This is an General … software, so bugs are expected. If you encounter them, please …
Post: Enum Fields VS Varchar VS Int + Joined table: What is Faster?
January 24, 2008 By 27 Comments
…) NOT NULL, PRIMARY KEY (id), KEY state_id (state_id) ) ENGINE=MyISAM; 4) Dictionary table for cities_join: CREATE TABLE IF NOT EXISTS `states` ( `id` tinyint(3) NOT NULL auto_increment, `name` char(40) NOT NULL, PRIMARY KEY (`id…
Comment: Why MySQL could be slow with large tables ?
May 27, 2009 By 139 Comments
… different table named iplist CREATE TABLE IF NOT EXISTS `iplist` ( `id` int(11) unsigned NOT NULL AUTO_INCREMENT, `code` varchar(2) NOT NULL, `code_3` varchar(3) NOT NULL, `name` varchar(255) NOT…
Post: Another scalability fix in XtraDB
January 23, 2009 By 13 Comments
… 5 against table CREATE TABLE IF NOT EXISTS sbtest ( id int(10) unsigned NOT NULL auto_increment, name varchar(64) NOT NULL default ”, email varchar(64) NOT NULL default… (id) ) CREATE INDEX email_idx on sbtest(email); CREATE INDEX country_id_idx on sbtest(country_id,state_id,city); with table size…
Post: PBXT benchmarks
April 8, 2007 By 14 Comments
… extra indexes. CREATE TABLE IF NOT EXISTS `$tableName` ( `id` int(10) unsigned NOT NULL auto_increment, `name` varchar(64) NOT NULL default ”, `email` varchar(64) NOT NULL default… all scalability fixes exist in 5.1.16 tree. I think InnoDB team should solve this problem, I do not know Oracle…
Comment: Shard-Query adds parallelism to queries
November 22, 2010 By 16 Comments
… TEMPORARY table serially. When using the ‘store’ method, a CONCRETE table is used, which is visible to multiple sessions. The table is created with CREATE TABLE IF NOT EXISTS, so the first query to register results will create the table…
