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Search Results for: recovering

Recovering temporal types in MySQL 5.6: TIME, TIMESTAMP and DATETIME

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 …

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Recovering from a bad UPDATE statement

Did you just run an UPDATE against your 10 million row users table without a WHERE clause?  Did you know that in MySQL 5.5 that sometimes you can recover from a bad UPDATE statement?  This …

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Recovering Linux software RAID, RAID5 Array

Dealing with MySQL you might need to deal with RAID recovery every so often. Sometimes because of client lacking the proper backup or sometimes because recovering RAID might improve recovery, for example you might get …

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Recovering CREATE TABLE statement from .frm file

So lets say you have .frm file for the table and you need to recover CREATE TABLE statement for this table. In particular when we do Innodb Recovery we often get .frm files and some …

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Recovering Innodb table Corruption

Assume you’re running MySQL with Innodb tables and you’ve got crappy hardware, driver bug, kernel bug, unlucky power failure or some rare MySQL bug and some pages in Innodb tablespace got corrupted. In such cases …

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High-load clusters and desynchronized nodes on Percona XtraDB Cluster

There can be a lot of confusion and lack of planning in Percona XtraDB Clusters in regards to nodes becoming desynchronized for various reasons.  This can happen a few ways: An IST or SST joining …

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MySQL is crashing: a support engineer’s point of view

In MySQL QA Episode #12, “MySQL is Crashing, now what?,” Roel demonstrated how to collect crash-related information that will help Percona discover what the issue is that you are experiencing, and fix it. As a Support …

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Bypassing SST in Percona XtraDB Cluster with binary logs

In my previous post, I used incremental backups in Percona XtraBackup as a method for rebuilding a Percona XtraDB Cluster (PXC) node without triggering an actual SST. Practically this reproduces the SST steps, but it …

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Tips from the trenches for over-extended MySQL DBAs

This post is a follow-up to my November 19 webinar, “Tips from the Trenches: A Guide to Preventing Downtime for the Over-Extended DBA,” during which I described some of the most common reasons DBAs experience …

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How TokuMX Secondaries Work in Replication

As I’ve mentioned in previous posts, TokuMX replication differs quite a bit from MongoDB’s replication. The differences are large enough such that we’ve completely redone some of MongoDB’s existing algorithms. One such area is how …

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