Jul 26, 2013 |
Insight for DBAs, Insight for Developers, MySQL
If we have InnoDB pages there are two ways to learn how many records they contain: PAGE_N_RECS field in the page header Count records while walking over the list of records from infimum to supremum In some previous revision of the recovery tool a short summary was added to a dump which is produced by […]
Jul 16, 2013 |
Insight for DBAs, MySQL
MySQL 5.6 introduces a new feature – microseconds resolution in some temporal types. As of 5.6.4 TIME, TIMESTAMP and DATETIME can have a fractional part. To create a field with subseconds you can specify precision in brackets: TIME(3), DATETIME(6) etc. Obviously, the new feature requires the format change. All three types may now have a […]
Apr 25, 2013 |
Insight for DBAs, MySQL
After nearly every recovery case the same question arises: How many MySQL records were recovered and how many were lost. Until now there was no way to answer the question without manual investigation. As it turned out a small change can make a big difference. There are two ways to know how many records an […]
Apr 22, 2013 |
Insight for DBAs, MySQL
To recover a dropped or corrupt table with Percona Data Recovery Tool for InnoDB you need two things: media with records(ibdata1, *.ibd, disk image, etc.) and a table structure. Indeed, there is no information about the table structure in an InnoDB page. Normally we either recover the structure from .frm files or take it from […]
Aug 22, 2012 |
MySQL
In a very popular data loss scenario a table is dropped and empty one is created with the same name. This is because mysqldump in many cases generates the “DROP TABLE” instruction before the “CREATE TABLE”:
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DROP TABLE IF EXISTS `actor`; /*!40101 SET @saved_cs_client = @@character_set_client */; /*!40101 SET character_set_client = utf8 */; CREATE TABLE `actor` ( `actor_id` smallint(5) unsigned NOT NULL AUTO_INCREMENT, `first_name` varchar(45) NOT NULL, `last_name` varchar(45) NOT NULL, `last_update` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, PRIMARY KEY (`actor_id`), KEY `idx_actor_last_name` (`last_name`) ) ENGINE=InnoDB AUTO_INCREMENT=201 DEFAULT CHARSET=utf8; /*!40101 SET character_set_client = @saved_cs_client */; |
If there were no subsequent CREATE TABLE the recovery would be trivial. Index_id of the PRIMARY index of […]
Aug 10, 2012 |
Insight for DBAs, MySQL
Recently I had a case when a customer deleted the InnoDB main table space – ibdata1 – and redo logs – ib_logfile*. MySQL keeps InnoDB files open all the time. The following recovery technique is based on this fact and it allowed to salvage the database. Actually, the files were deleted long time ago – […]
May 13, 2011 |
MySQL
There are two ways InnoDB can organize tablespaces. First is when all data, indexes and system buffers are stored in a single tablespace. This is typicaly one or several ibdata files. A well known innodb_file_per_table option brings the second one. Tables and system areas are split into different files. Usually system tablespace is located in […]
Sep 27, 2010 |
MySQL, Percona Software
Dear Community, Percona Server version 5.1.50-rel11.4 is now available for download. The changes in this release include: New features The primary purpose of this release is to update to the latest version of MySQL 5.1. Percona Server 5.1.50-rel11.4 is now based on MySQL 5.1.50. Fixed bugs innodb_use_sys_stats_table – The
table is now used only […]
Sep 15, 2010 |
MySQL, Percona Software
Dear Community, Starting with this release, we introduce a new release model for Percona Server. From now on, we will have both Stable and Release Candidate releases. Release Candidates will introduce new features not yet available in Stable releases. Along with new features, our new 5.1.49-12.0 RC contains a couple of patches from the Facebook-MySQL […]
Sep 10, 2010 |
Percona Software
Dear Community, Percona Server version 5.1.49-rel11.3 is now available for download. The changes in this release include: New features Percona Server 5.1.49-rel11.3 is based on MySQL 5.1.49. A new variable was introduced: innodb_use_sys_stats_table. If ON, the table’s statistics are stored statically in the internal table SYS_STATS. The table is populated with the ANALYZE TABLE command. […]
Jul 01, 2010 |
Insight for DBAs, MySQL
For a long time long types like BLOB, TEXT were not supported by Percona InnoDB Recovery Tool. The reason consists in a special way InnoDB stores BLOBs. An InnoDB table is stored in a clustered index called PRIMARY. It must exist even if a user hasn’t defined the primary index. The PRIMARY index pages are […]
Jun 21, 2010 |
MySQL, Percona Software
Dear Community, Percona Server version 5.1.47-rel11.0 is available for download now. The changes in this release include: New features Percona Server is now based on MySQL 5.1.47, and XtraDB is now based on InnoDB plugin 1.0.8. XtraDB now uses the fast recovery code released in InnoDB Plugin version 1.0.8, instead of Percona’s earlier fast-recovery code. […]
May 07, 2010 |
MySQL, Percona Software
Dear Community, Percona Server 5.0.90, release 21 is available for use. Comparing to the previous release it has following new features: The build is based on MySQL-5.0.90 Fixed bugs: Fixed Bug #539190 Percona-XtraDB package doesn’t allow libmysqlclient15off Fixed Bug #479106 mysql-5.0.87 + patches-5.0.86 compile fail in ubuntu 9.10 (karmic) Fixed tests mysql, mysql_upgrade, ssl* See […]
Apr 13, 2010 |
MySQL, Percona Software
Dear Community, Today we are pleased to announce the release 10 of Percona Server with XtraDB storage engine. Since the previous release 9.1 there are following changes
Apr 13, 2010 |
MySQL, Percona Software
Dear Community, The notice is hereby given that next version 1.2 of XtraBackup software is released. The list of changes in this version includes: Changelog: XtraBackup supports now XtraDB 10 tar4ibd supports variable page size and fast_checksum of XtraDB Supported 32bit platform for Centos 5, Centos 4, Debian lenny and etch, Ubuntu Karmic, Jaunty, Intrepid, […]
Mar 24, 2010 |
MySQL, Percona Software
Dear Community, It is time to announce the next version of backup software from Percona – XtraBackup 1.1. The list of changes in version 1.1 includes: Changelog: XtraBackup is built on a base of MySQL 5.1.44 with InnoDB plugin 1.0.6 Added –host option tar4ibd can treat over 64GB file tar4ibd is default method for stream, […]
Mar 14, 2010 |
MySQL, Percona Software
Dear Community, We are announcing today the new version 9.1 of XtraDB storage engine. The name of binaries has changed to Percona-XtraDB. It is applicable to all packages including RPM, DEB and tar.gz packages. New features in version 9.1: MySQL 5.1.43 is taken as the basis packages name changed to Percona-XtraDB Enabled support of SSL […]
Jan 13, 2010 |
MySQL, Percona Software
Dear Community, As of today Release 9 of XtraDB storage engine is available. The release includes following new features: The release is base on 1.0.6 version of InnoDB plugin. MySQL 5.1.42 as a base release Separate purge thread and LRU dump is implemented (this feature was actually added in Release 8, but somehow it was […]
Dec 09, 2009 |
MySQL, Percona Software
Dear Community, As of today release 1.0 is available. In this release there are following changes: Changelog: XtraBackup is ported to Windows. The .MSI package as well as .tar.gz is available for 32 bit platform Be more verbose on reporting scp errors Fixed bugs: Bug #463691 in Percona-XtraBackup: “innobackupex-1.5.1 –help goes to STDERR” Bug #463709 […]
Nov 18, 2009 |
MySQL, Percona Software
Dear Community, We are pleased to present the 20th build of MySQL server with Percona patches. Comparing to the previous release it has following new features: The build is based on MySQL-5.0.87 innodb_rw_lock.patch is ported from InnoDB Plugin 1.0.3 To be compatible with RedHat RPM repository, the naming scheme has changed to
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<rpm name>-<mysql version>-<percona build version>.<buildnumber>.<redhat version>.<architecture>.rpm |
Example:
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MySQL-server-percona-5.0.87-b20.29.rhel5.x86_64.rpm |
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