… a presentation on “MySQL Query Patterns, Optimized” for Percona MySQL Webinars. If you missed it…rows involves some compromise, either of performance, or of accuracy of randomness. The ORDER BY… and reinitializing the sequence after making certain insert/update/delete operations. If you have a …
Post: Is your MySQL buffer pool warm? Make it sweat!
April 16, 2013 By 6 Comments
…_server:3307/slow | percona-playback –mysql-host 127.0.0.1 –mysql-username playback –mysql-password PaSSwOrd –mysql-schema schema_name –query-log-stdin… traffic. This is an important step because update statements that match no rows or insert statements that have duplicate key errors may be…
Post: Follow these basics when migrating to Percona XtraDB Cluster for MySQL
May 1, 2013 By 10 Comments
…(PXC) for MySQL is a hot thing right now and…’re more likely to either suffer failure or issues that prevent them from moving forward…. log_slave_updates is REQUIRED You need to have log_slave_updates enabled on …cluster, this is to avoid collisions when INSERTs are happening on not only a single …
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
…replication is right for their application or not. Facts about Galera replication …MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL …updates groups with some metadata: BEGIN; INSERT INTO users_groups (user_id, group_id) VALUES (100, 1); UPDATE…
Comment: MySQL Partitioning - can save you or kill you
April 30, 2013 By 45 Comments
… Percona or MariaDB. (Re #4) There are _no_ parallel queries (within a single connection) anywhere in any ‘free’ variant of MySQL. PARTITIONs… would argue that single-row queries (SELECT, INSERT, DELETE, UPDATE) are similar in speed between PARTITIONed or non-PARTITIONed. When PARTITIONed, first it… PARTITIONing. I go into more details (and code) here: http://mysql.rjweb.org/doc.php/partitionmaint The third use case for…
Post: Benchmarking Percona Server TokuDB vs InnoDB
May 7, 2013 By 32 Comments
…which should produce updates in-place (I will use INSERT .. ON DUPLICATE KEY UPDATE statements for …this size will be the same or worse, but will require 1TB in …insert-roll-2, command line to run: sysbench –test=insert_roll.lua –oltp-table-size=10000 –mysql-user=root –oltp-tables-count=32 –mysql…
Comment: Follow these basics when migrating to Percona XtraDB Cluster for MySQL
May 2, 2013 By 10 Comments
… *, UPDATE host, INSERT) a few times than trying to recreate the grants. I don’t know whether it’s even possible or wheter Oracle is planning to move the mysql db to InnoDB tables (try googling for that), but it would be a nice addition… Thanks for the log-slave-updates…
Post: Edge-case behavior of INSERT...ODKU
October 27, 2012 By 6 Comments
…table were almost exclusively INSERT … ON DUPLICATE KEY UPDATE (INSERT ODKU), with the columns from the INSERT part of the…be considered as being defined first. So, MySQL checks our INSERT, sees that the next auto-inc value…a day, and we get 33.1 days, or a little over 4 weeks. Coincidence? I think …
Post: Implications of Metadata Locking Changes in MySQL 5.5
February 1, 2013 By 9 Comments
…L5cLURMBAAAALwAAAAUDAAAAABEAAAAAAAEABHRlc3QABHRlc3QAAwMD/gL+CQY= L5cLURgBAAAAOAAAAD0DAAAAABEAAAAAAAEAA///+AIAAAAAAAAAA2JhcvgCAAAAAAAAAANob3A= ‘/*!*/; ### UPDATE test.test ### WHERE ### @1=…lock bringing down the MySQL server or causing all the… (0.09 sec) session1 > insert into t1 values(null); …
Post: Announcing Percona Server for MySQL version 5.5.29-30.0
February 26, 2013 By Leave a Comment
… #1017192 (Sergei Glushchenko). The server could crash when executing an INSERT or UPDATE statement containing BLOB values for a compressed table. This regression… prefix of another command line option innodb_changed_pages_limit. MySQL option handling would then shadow the former with the latter…
