… “MySQL Query Patterns, Optimized” for Percona MySQL Webinars. If …great questions. I answered as many as we had time for…using a temporary table to store an interim result set, and then use that to ultimately produce the result…index. Example: WHERE (last_name, first_name) = (‘Karwin’, ‘Bill’); Q: …
Post: Percona Server 5.6.11-60.3 first Release Candidate now available
June 3, 2013 By 3 Comments
…width=”247″] Percona Server for MySQL version 5.6.11-… calloc() directly instead of using InnoDB heap allocation. This…file name components in a bitmap file name could stop…result set. Bug fixed #1185040. The INNODB_CHANGED_PAGES table… overhead from the Handle Corrupted Tables check as it was missing …
Post: How to recover table structure from InnoDB dictionary
April 22, 2013 By 4 Comments
… thus will spoil the result. That’s why I …name/table_name e.g. sakila/actor. `ID` is a table identifier. We will need the table id to find indexes of the table. mysql…table. If explicitely defined its `NAME` is PRIMARY. If the primary key is not defined InnoDB will use a unique secondary index as…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
…Results: First of all, we used a smaller dataset for this benchmarks round, since reportedly Dimitri was using 8 tables…MySQL 5.6 virtually eliminates contention on the mutex protecting the list of transactions, its applicability is quite limited. Namely… read-only server. As soon as there is a non…
Post: Galera Flow Control in Percona XtraDB Cluster for MySQL
May 2, 2013 By 5 Comments
…using Donor/Desynced nodes, particularly when using…as soon as possible. An example configuration tuning flow control in a master/slave cluster might be: mysql… the result of some…TABLES WITH READ LOCK on node3: [root@node3 ~]# myq_status wsrep Wsrep Cluster Node Queue Ops Bytes Flow Conflct time name…
Post: Be productive with the MySQL command line
December 21, 2012 By 14 Comments
…results. It can be annoying but it is easily solved by using the pager command: mysql> pager more PAGER set to ‘more’ mysql…mysql> tee queries.log Logging to file ‘queries.log’ mysql> use sakila Reading table information for completion of table and column names…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 20 Comments
…table_id: 28 mview_id: 21 mview_table_name: customers mview_table_schema: demo mview_table_alias: c mview_join_condition: USING…
Post: Eventual Consistency in MySQL
November 18, 2011 By 8 Comments
…mysql> SELECT CONCAT( ‘SELECT ‘, GROUP_CONCAT(DISTINCT CONCAT(K.CONSTRAINT_NAME, ‘.’, P.COLUMN_NAME, ‘ AS `’, P.TABLE_SCHEMA, ‘.’, P.TABLE_NAME, ‘.’, P.COLUMN_NAME…result set, it shows us which rows in Bar are orphans. mysql> INSERT INTO Foo (A,B) VALUES (111,2222), (333,444); mysql…You can use …
Post: Quickly finding unused indexes (and estimating their size)
December 5, 2012 By 2 Comments
…use that information: mysql> drop view if exists droppable_indexes; mysql> create view droppable_indexes as select all_indexes.table_schema as table_schema, all_indexes.table_name as table_name…
Post: Side load may massively impact your MySQL Performance
November 13, 2011 By 7 Comments
…mysql –mysql-host=localhost –mysql-table-engine=innodb –mysql-db=test –oltp-table-name=md_cache_test_small –oltp-table-size=1100000 –mysql-user=msandbox –mysql-password=msandbox –mysql-socket=/tmp/mysql…
