… default should be changed to ‘0‘ which means “choose automatically”, which in turn means “choose depth 7“. Is this what your blog… if we want a simple magic threshold, the number is “7“. This is also confirmed by looking at the graph of… potential pitfalls with the change to plan pruning in MySQL 5.6. Ideally, the server should analyze the query and should…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 9 Comments
… for MySQL 5.6, increase of 0.02s. But the query times for MariaDB 5.5 are greater than both MySQL 5.5 and MySQL 5.6…_o_orderdate,i_o_custkey i_o_custkey 5 dbt3.customer.c_custkey 7 100.00 Using where 1 SIMPLE lineitem ref… is no difference in query times between MySQL 5.5 and MySQL 5.6/MariaDB 5.5 This is another area of improvement in the…
Post: Some fun with R visualization
February 23, 2012 By 5 Comments
… are results for 4 and 16 tables cases running MySQL 5.5.20. Let me remind how I do measurements. I run…
Comment: How to recover a single InnoDB table from a Full Backup
March 22, 2012 By 7 Comments
… been detected. InnoDB: Progress in %: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17… 99 100 done. 120323 4:38:52 InnoDB: Error: page 0 log sequence number 6094071743825 InnoDB: is in the future! Current… log files. See InnoDB: http://dev.mysql.com/doc/refman/5.5/en/forcing-innodb-recovery.html InnoDB: for more information.
Comment: How to replace a NDB node on EC2
February 22, 2012 By 10 Comments
….0.0.1 (mysql-5.1.56 ndb-7.1.13, Nodegroup: 0, Master) id=5 @10.0.0.3 (mysql-5.1.56 ndb-7.1.913 starting, Nodegroup: 0) ndb_mgm> all status; Node 4: started (mysql-5.1.56 ndb-7…
Post: Joining many tables in MySQL - optimizer_search_depth
April 20, 2012 By 5 Comments
… one, yet you could notice EXPLAIN itself was taking same 5 seconds, which points to problem with optimizer performance. Note though… was wondering if 0 is automatic selection why do we have value of 62 being default in MySQL 5.5 which can produce… users do not join lots of tables (less than 7) when using 0 as default value would not impact them. For people…
Post: Faster Point In Time Recovery with LVM2 Snaphots and Binary Logs
February 23, 2012 By Leave a Comment
…Base installs of Ubuntu 11.04 (Natty) and CentOS 5.7 includes packages with this feature, previous releases might…TABLES; +———————+ | Tables_in_employees | +———————+ … | salaries | … +———————+ 6 rows in set (0.05 sec) Success! Your salaries data is back. …
Comment: Avoiding auto-increment holes on InnoDB with INSERT IGNORE
March 11, 2012 By 7 Comments
….22 change autoincrement mod http://dev.mysql.com/doc/refman/5.1/en/innodb-auto-increment-handling.html I have the… to your my.ini file. # =0 is traditional lock mode == > funcionality of auto_increment like before 5.1.22 # =1 is default… 1; 1 Peter 2 Oto 3 Jan 4 Romco ===> not 7 Romco as before
Comment: InnoDB thread concurrency
March 19, 2012 By 4 Comments
…like follows: ——– FILE I/O ——– I/O thread 0 (thread id: 18578) state: waiting for completed …completed aio requests (read thread) I/O thread 5 (thread id: 18583) state: waiting for completed …completed aio requests (write thread) I/O thread 7 (thread id: 18585) state: waiting for completed …
Post: TPC-H Run on MySQL 5.1 and 6.0
April 10, 2008 By 16 Comments
… than 1 MySQL 6.0 is faster if more than 1 slower: Query MySQL 5.0.23 MySQL 6.0.4Ratio Query1370.50372.161… you can get an idea – This system has geomean of 7.7 sec for Power test which is good order of magnitude… more time to complete the queries: Query MySQL 5.0.23 MySQL 6.0.4Ratio Query13784.453737.540.99 Query2NANANA Query3NANANA Query4NANANA Query5NANANA…
