…constantly referring to the amazing MySQL manual, especially the option and variable reference table. …_tmp_tablesblogpercona.commanual datadirblogpercona.commanual date_formatblogpercona.commanual datetime_formatblogpercona.commanual debugblogpercona.commanual debug_syncblogpercona.commanual debug_…
Post: When is MIN(DATE) != MIN(DATE) ?
September 4, 2012 By 5 Comments
… INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY, uid INT UNSIGNED NOT NULL, update_time DATETIME NOT NULL, …. INDEX `uid` (uid, update_time), INDEX `bar` (some… to force MySQL to use a different index. Imagine our surprise when we tried a FORCE INDEX on (bar) or an IGNORE INDEX(uid…
Post: Logging Foreign Key errors
September 27, 2012 By Leave a Comment
… the information: CREATE TABLE foreign_key_errors ( ts datetime NOT NULL, error text NOT NULL, PRIMARY KEY (ts) ); 2- Run the tool as…”) ON DELETE CASCADE The index in the foreign key in table is “PRIMARY” See http://dev.mysql.com/doc/refman/5.5… by an index that was referenced by the FK, a PRIMARY KEY. So, the command that causes the error was: mysql> ALTER…
Comment: COUNT(*) vs COUNT(col)
April 25, 2007 By 45 Comments
…index | NULL | PRIMARY | 8 | NULL | 424672 | Using index | +—-+————-+————-+——-+—————+———+———+——+——–+————-+ 1 row in set (0.11 sec) mysql…
Post: Benchmarking single-row insert performance on Amazon EC2
May 16, 2012 By 17 Comments
… RAID 10. Now let’s come to the MySQL configuration. MySQL Configuration I used Percona Server 5.5.22-55 …index` ( `transactionid` int(11) NOT NULL AUTO_INCREMENT, `dateandtime` datetime DEFAULT NULL, `cashregisterid` int(11) NOT NULL, `customerid` int(11) NOT NULL, `productid` int(11) NOT NULL…
Comment: Real-Life Use Case for "Barracuda" InnoDB File Format
April 24, 2008 By 11 Comments
…at` datetime DEFAULT NULL, `updated_at` datetime DEFAULT NULL, `query_count` int(11) DEFAULT ’0′, `short_html` text, PRIMARY KEY (`id`), KEY `index_document_queries_on_word_document_id` (`word_document_id`) ) ENGINE=InnoDB mysql> show table status like ‘…
Comment: How to find wrong indexing with glance view
March 8, 2010 By 27 Comments
…not null, operator_id smallint unsigned not null, order_amount decimal(10, 4) not null, order_date datetime not null, last_updated timestamp not null …operators. MySQL will create the following indexes: unique index on order_id index on item_type_id index on locale_id index on currency_id index …
Post: Copying InnoDB tables between servers
July 31, 2009 By 11 Comments
…NULL, `ol_delivery_d` datetime default NULL, `ol_quantity` tinyint(4) default NULL, `ol_amount` decimal(6,2) default NULL… started. InnoDB: import: 2 indexes are detected. InnoDB: Progress in …. When finished quick check mysql> select count(*) from order_line; +———-+ | count(*) | +———-+ | …
