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Search Results for: ibdata1 recovery mysql

Examining the TokuDB MySQL storage engine file structure

As we know different storage engines in MySQL have different file structures. Every table in MySQL 5.6 must have a .frm file in the database directory matching the table name. But where the rest of …


How to recover an orphaned .ibd file with MySQL 5.6

A few years ago Yves Trudeau and Aleksandr Kuzminsky wrote posts about different ways for recovering orphaned .ibd files: Connecting orphaned .ibd files A recovery trivia or how to recover from a lost ibdata1 file …


Recovery after DROP & CREATE

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 …


Recovery deleted ibdata1

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 …


A recovery trivia or how to recover from a lost ibdata1 file

A few day ago, a customer came to Percona needing to recover data. Basically, while doing a transfer from one SAN to another, something went wrong and they lost the ibdata1 file, where all the …


New SpecJAppServer results at MySQL and Sun.

As you likely have seen Sun has posted the new SpecJAppServer Results More information from Tom Daly can be found here These results are quite interesting for me as I worked on some of the …


Percona Server with TokuDB (beta): Installation, configuration

My previous post was an introduction to the TokuDB storage engine and aimed at explaining the basics of its design and how it differentiates from InnoDB/XtraDB. This post is all about motivating you to give it …


Incremental backups with log archiving for XtraDB

Percona Server 5.6.11-60.3 has introduced a new feature called Log Archiving for XtraDB. This feature makes copies of the old log files before they are overwritten, thus saving all the redo log for a write …


How to move the InnoDB log sequence number (LSN) forward

This post focuses on the problem of the InnoDB log sequence number being in the future. Preface: What is an InnoDB log sequence number? The Log sequence number (LSN) is an important database parameter used by …


Checking B+tree leaf nodes list consistency in InnoDB

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 …