…’m using the closure table hierarchy to store regions in a database using MySQL and I’m wondering how can I create a unordered list with indentation (for each level) with the datas. I… or less in the future. How can reordered the receive data correctly to do so ? I saw the article with the…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
… is a lot larger problems with MySQL 5.5 with addition of user variables, stored procedures, prepared statements etc which…current MEMORY tables: mysql> select sum(data_length+index_length) from information_schema.tables where engine=’memory’; +——————————-+ | sum(data_length+index…
Post: How FLUSH TABLES WITH READ LOCK works with Innodb Tables
March 23, 2012 By 20 Comments
… the table. mysql> show processlist; +——-+——+———–+———-+————+——+——————————+——————————+———–+—————+———–+ | Id | User | Host | db…, stored procedures etc (which are stored …when backing up data from the slave…
Post: Best kept MySQLDump Secret
March 23, 2012 By 11 Comments
… Transactions however apply to DATA which is stored in this table and so data which was inserted after …data. Here is example: SESSION1: mysql> show tables; +——————–+ | Tables_in_dumptest | +——————–+ | A | | B | | C | +——————–+ 3 rows in set (0.00 sec) mysql…
Post: Testing MySQL column stores
August 16, 2010 By 15 Comments
… opportunity to do some testing on a large data set against two MySQL column-store storage engines. I’d like to note that… Edition on a 950GB data set. The first first part of my analysis focused on testing specific MySQL functionally with Infobright’s… some of the queries. ICE supports almost all of the MySQL aggregation functions. Notably, GROUP_CONCAT is not supported, which is…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 12 Comments
… MySQL stored procedure API, called the SQL_API which is used to define the view. These stored procedures maintain the Flexviews data dictionary. The data…. This function reads the meta-data stored in the Flexviews data dictionary. It returns the SQL which represents the data stored in the view. This…
Post: Statement based replication with Stored Functions, Triggers and Events
December 16, 2011 By 3 Comments
…(this_year())’ STORED PROCEDURES The behaviour of stored procedures and functions are completely different. If our stored procedure write data to our … stored procedures in your slaves servers. Example: mysql> create procedure this_pyear() BEGIN INSERT INTO t VALUES(YEAR(CURDATE())); END;// mysql> …
Post: Data mart or data warehouse?
July 15, 2010 By 13 Comments
… with and without aggregation over multiple MySQL storage engines at various data scales. What is a data warehouse? It turns out that this… tools. To me, the definition of data warehouse is “A relational database schema which stores historical data and metadata from an operational system…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
…. Now, Valgrind does not need much introduction, especially to the MySQL server developers. The Valgrind Memcheck tool, which is synonymous with… the stores might be lost, with the counter values slightly smaller than they should be in the end. ==9090== Possible data race… 0x6A5E0C: JOIN::exec() (sql_select.cc:1863) ==9090== by 0x6A7D72: mysql_select(THD*, Item***, TABLE_LIST*, unsigned int, List
Post: How to recover a single InnoDB table from a Full Backup
January 25, 2012 By 7 Comments
…mysql/data/employees/ Import the new tablespace: mysql> set FOREIGN_KEY_CHECKS=0; mysql> ALTER TABLE salaries IMPORT TABLESPACE; mysql> set FOREIGN_KEY_CHECKS=1; mysql…this exports essential information from main tablespace which is not stored in .ibd file. innodb_import_table_from_xtrabackup=1 …
