… #1171941. Fixed the CVE-2012-5627 vulnerability, where an unprivileged MySQL account owner could perform brute-force password guessing attack on… the MySQL 5.6 version, which removed MyISAM internal temporary table mutex contention. Bug fixed #1179978. Release notes for Percona Server for MySQL 5…
Post: MySQL Query Patterns, Optimized - Webinar questions followup
June 3, 2013 By 2 Comments
… are other drawbacks to using temporary tables in this way, for example when using replication, a temporary table could vanish if the slave restarts… temporary table to count the movies per production year for each kind_id. It was more efficient in this case to force MySQL… more rows. But by avoiding the temporary table, and making lookups to the `kind_types` table by primary key, the result was a…
Comment: Replication in MySQL 5.6: GTIDs benefits and limitations - Part 1
June 10, 2013 By 8 Comments
… to simply switch from regular MySQL replication to using replication using GTIDs 1. Temporary tables – CREATE and DROP TEMPORARY tables are not supported inside transaction. 2. Updates involving non-transactional storage engines – It is not possible to mix non-transactional tables…
Post: Percona XtraDB Cluster 5.5.30-23.7.4 for MySQL now available
April 17, 2013 By 2 Comments
… when DROP TEMPORARY TABLE statement was used, but it will still replicate in case DROP TABLE statement is used on a temporary table. Bug fixed… leave a slave hanging. Bug fixed #1130888 (Seppo Jaakola). If MySQL replication threads were started before running wsrep recovery, this would…
Post: Webinar: MySQL 5.6 Performance Schema
May 13, 2013 By 5 Comments
….m. Pacific, I’ll be leading a Webinar titled, “Using MySQL 5.6 Performance Schema to Troubleshoot Typical Workload Bottlenecks.” In… of focus include: Bottlenecks with Disk IO Problems with excessive temporary tables and external sorts Excessive internal mutex contention Slow queries due…
Comment: TMP_TABLE_SIZE and MAX_HEAP_TABLE_SIZE
April 4, 2013 By 17 Comments
… i converted databases from MyISAM to InnoDB, mysql tunning script gives below results for temp table , server has 4G ram, which almost… should increase your tmp_table_size and/or max_heap_table_size to reduce the number of disk-based temporary tables Note! BLOB and TEXT columns are not allow in memory tables. If…
Post: Can MySQL temporary tables be made safe for statement-based replication?
May 26, 2008 By 8 Comments
… tables. Thus, I claimed, there’s no alternative but to eliminate temporary tables. This problem may not exist for row-based replication in MySQL…_log_pos: 288 Info: use `test`; drop temporary table test.t *************************** 7. row *************************** Log_name: mysql-bin.000011 Pos: 567 Event_type: Xid…, I still don’t see any way to use temporary tables with MySQL statement-based replication without some risk of breaking slaves. At…
Post: How much overhead is caused by on disk temporary tables
August 16, 2007 By 26 Comments
… table size, even when all data fits in memory MEMORY temporary tables can be 10-100 times faster than disk based MyISAM tables Hopefully MySQL will implement support of dynamic rows for MEMORY tables…
Post: MySQL EXPLAIN limits and errors.
July 24, 2006 By 6 Comments
… at which stage MySQL actually perform the sort or creates temporary table and so how much rows will be stored to temporary table. Sometimes it… rows by reading data from other tables. No information about using disk for sort or temporary tables MySQL always calls it “filesort” even if it is done in memory. Also it would not tell you if temporary table will…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 5 Comments
… better as you can query temporary tables too: mysql> select sum(data_length+index_length) from information_schema.global_temporary_tables where engine=’memory’; +——————————-+ | sum… which temporary tables (both in memory and not): mysql> select * from information_schema.global_temporary_tables \G *************************** 1. row *************************** SESSION_ID: 7234 TABLE_SCHEMA: test TABLE_NAME…
