…optimizations. Batched Key Access Traditionally, MySQL always uses Nested Loop Join to join two or more tables…table we created earlier. This step is known as probe step. This join algorithm works best for highly selective queries, and obviously when…of these buffers should be increased appropriately …
Comment: Joining many tables in MySQL - optimizer_search_depth
April 23, 2012 By 6 Comments
…ago, when I was just hired at MySQL. The assumptions about what are typical MySQL may …of tables) that can be optimized in reasonable time. I reached the conclusion that if we …We still have to investigate the potential pitfalls with the change to plan pruning in MySQL 5.6. Ideally, the server should…
Post: Economics of Performance Optimization
March 13, 2008 By 9 Comments
… These questions are: Should we Optimize Application or get more Hardware ? Should we do things ourselves or…proper indexes or tuning couple of MySQL settings. When low hanging fruits are fixed you…application changes such as building summary tables, significant schema changes, use of replication, …
Post: How to Monitor MySQL with Percona's Nagios Plugins
February 22, 2012 By 8 Comments
…table-checksum tool from Percona Toolkit can generate table checksums, and the pmp-check-pt-table-checksum plugin can alert when…or poorly optimized queries…any other, should only…when the problem has grown much more serious. You can use the pmp-check-mysql-status plugin to alert when… releases we …
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…when I’m examining the status values for Created_tmp_tables and Created_disk_tmp_tables, I’ll paste in mysql…. Schema, query, and index optimization Analyzing and optimizing a server’s table and index structures, and the …changes that can or should be made at a much higher level. If we see that the …
Post: MySQL Users Conference - Innodb
May 9, 2007 By 6 Comments
…example will LOAD DATA INFILE be optimized same way as for MyISAM tables by separate phase of …should mention Innodb is being blamed for a lot of “Gotches” while many of them come from MySQL limits at the time when… from Google released so many MySQL patches so we can call patched version GoogleSQL. …
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 27 Comments
… performance optimization from the standpoint of response time measurements, which you should…we optimize-by-surrogate-measure a time or two and it appears to work — so we…’s dedicated to MyISAM tables. Consider your mixture of storage …This is a shame. When you are new to MySQL, trying to configure…
Post: Recovering Innodb table Corruption
July 4, 2008 By 19 Comments
…tables): mysql> optimize table test; +———–+———-+———-+———————————-+ | Table | Op | Msg_type | Msg_text | +———–+———-+———-+———————————-+ | test.test | optimize…
Post: Should you move from MyISAM to Innodb ?
January 12, 2009 By 53 Comments
… Innodb. Application Readiness Application should be ready to work with…the drawbacks side we see significantly large table size (especially if …common paths in the MySQL server – in particular Optimizer may have …when use other tables when it really gives substantial gains. I would not switch table…
Post: Flexviews - part 3 - improving query performance using materialized views
April 4, 2011 By 12 Comments
…the table name specified in each statement. You should try…date,”%Y%m”)’,'sale_when‘); CALL flexviews.add_expr(@…after the incremental one. We can use the new MV…optimization which is required to efficiently refresh MV which use those aggregate functions. Now I delete some line items from orders: mysql…
