You searched for delete rows innodb - MySQL Performance Blog

Is your MySQL buffer pool warm? Make it sweat!

April 16, 2013 By Peter Boros 6 Comments

Today’s blog post diving into the waters of the MySQL buffer pool is a cross-post from Groupon’s engineering blog, and is Part 1 of 2. Thank you to Kyle Oppenheim at Groupon for contributing to this project and post. We’ll be posting Part 2 on Thursday. I’ll be at the Percona Live MySQL Conference and [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL, Percona Software Tagged With: Groupon, Kyle Oppenheim, MySQL buffer pool, MySQL High Availability, Percona Playback, Peter Boros, Replaying Queries, Warm standby server

InnoDB Full-text Search in MySQL 5.6 (part 1)

February 26, 2013 By Ernie Souhrada 1 Comment

I’ve never been a very big fan of MyISAM; I would argue that in most situations, any possible advantages to using MyISAM are far outweighed by the potential disadvantages and the strengths of InnoDB. However, up until MySQL 5.6, MyISAM was the only storage engine with support for full-text search (FTS). And I’ve encountered many [...]

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: Ernie Souhrada, FTS, FullText Search, InnoDB, MyISAM, MySQL 5.6

Concatenating MyISAM files

November 19, 2012 By Yves Trudeau 5 Comments

Recently, I found myself involved in the migration of a large read-only InnoDB database to MyISAM (eventually packed). The only issue was that for one of the table, we were talking of 5 TB of data, 23B rows. Not small… I calculated that with something like insert into MyISAM_table… select * from Innodb_table… would take [...]

Filed Under: MySQL

Knowing what pt-online-schema-change will do

November 1, 2012 By Daniel Nichter 1 Comment

pt-online-schema-change is simple to use, but internally it is complex. Baron’s webinar about pt-online-schema-change hinted at several of the tool’s complexities. Consequently, users often want to know before making changes what pt-online-schema-change will do when it runs. The tool has two options to help answer this question: –dry-run and –print. When ran with –dry-run and –print, pt-online-schema-change changes nothing [...]

Filed Under: Insight for DBAs, Percona Software Tagged With: pt-online-schema-change

Full Text Search Webinar Questions Followup

August 24, 2012 By Bill Karwin 5 Comments

I presented a webinar this week to give an overview of several Full Text Search solutions and compare their performance. Even if you missed the webinar, you can register for it, and you’ll be emailed a link to the recording. During my webinar, a number of attendees asked some good questions. Here are their questions and my [...]

Filed Under: Events and Announcements, Insight for Developers, MySQL

Recovery after DROP & CREATE

August 22, 2012 By Aleksandr Kuzminsky 1 Comment

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”:

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 */;

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 [...]

Filed Under: MySQL Tagged With: drop table, InnoDB, Recovery

Recovery deleted ibdata1

August 10, 2012 By Aleksandr Kuzminsky 9 Comments

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 – [...]

Filed Under: Insight for DBAs, MySQL Tagged With: innodb recovery

DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL

June 22, 2012 By Ovais Tariq 33 Comments

Suppose you have turned on innodb_file_per_table (which means that each table has its own tablespace), and you have to drop tables in a background every hour or every day. If its once every day then you can probably schedule the table dropping process to run during off-peak hours. But I have seen cases where the [...]

Filed Under: Benchmarks, Insight for DBAs, MySQL

Load management Techniques for MySQL

May 6, 2012 By Peter Zaitsev 3 Comments

One of the very frequent cases with performance problems with MySQL is what they happen every so often or certain times. Investigating them we find out what the cause is some batch jobs, reports and other non response time critical activities are overloading the system causing user experience to degrade. The first thing you need [...]

Filed Under: Insight for DBAs, MySQL

InnoDB’s gap locks

March 27, 2012 By Miguel Angel Nieto 15 Comments

One of the most important features of InnoDB is the row level locking. This feature provides better concurrency under heavy write load but needs additional precautions to avoid phantom reads and to get a consistent Statement based replication. To accomplish that, row level locking databases also acquire gap locks. What is a Phantom Read A [...]

Filed Under: MySQL

Is your MySQL buffer pool warm? Make it sweat!

InnoDB Full-text Search in MySQL 5.6 (part 1)

Concatenating MyISAM files

Knowing what pt-online-schema-change will do

Full Text Search Webinar Questions Followup

Recovery after DROP & CREATE

Recovery deleted ibdata1

DROP TABLE and stalls: Lazy Drop Table in Percona Server and the new fixes in MySQL

Load management Techniques for MySQL

InnoDB’s gap locks

Search

Top Searches

Percona Webinars

ABOUT PERCONA

Percona MySQL Training

Percona Careers

SOFTWARE FROM PERCONA

SERVICES FOR MYSQL USERS

ABOUT THIS BLOG AND PERCONA