Does your dataset consist of InnoDB tables with large BLOB data such that the data is stored in external BLOB pages? Was the dataset created in MySQL version 5.1 and below and without using the InnoDB plugin, or with InnoDB plugin but with MySQL version earlier than 5.1.55? If the answer to both the questions are "YES" then it could very well be that you have a hidden corruption lying around in your dataset.
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Oracle has released the Critical Patch Update (CPU) advisory for January
The affected MySQL products are:
- Oracle MySQL Enterprise Monitor, versions 2.3, 3.0
- Oracle MySQL Server, versions 5.1, 5.5, 5.6
So this means that you should consider updating MySQL. For MySQL
Enterprise the updates should be available on My Oracle Support
and for the Community version the new versions are on the regular
download locations. I guess the official repositories are
For MySQL 5.6 you should upgrade to 5.6.15
For MySQL 5.5 you should upgrade to 5.5.35
For MySQL 5.1 you should upgrade to 5.1.73
If you use the MySQL release from your distribution …
While most of the talk recently has mostly been around the new changes in MySQL 5.6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the Metadata Locking related changes that were introduced in MySQL 5.5.3. It appears that the implications of Metadata Locking have not been covered well, and since there are still a large number of MySQL 5.0 and 5.1 installations that would upgrade or are in the process of upgrading to MySQL 5.5, I thought it necessary to discuss what these implications exactly are.
The post Implications of Metadata Locking Changes in MySQL 5.5 appeared first on ovais.tariq.
As we know, MySQL workbench is excellent GUI tool for managing MySQL DB servers, creating ERDs (Data Modelling) and for sql development. But with this GUI tool, we are getting some command-line utilities too like mysqldiskusage, mysqlindexcheck, mysqlfailover, mysqldiff, mysqldbcompare etc., Here, I’m describing mysqldiskusage utility, which is not only displays mysql db usage but … Continue Reading …[Read more]
mysqlslap is native mysql utility to check client load in MySQL server. It’s introduced in MySQl 5.1. It seems very useful as it has lots of options to check load of your server by running different kind of queries with specific iterations, specific concurrency. Output will give you how much max/min/avg time has been taken … Continue Reading …[Read more]
“Server log tables” is one of the finest feature in MySQL 5.1 version but It looks like people are not using this feature regularly or perhaps they are happy with files only. Here, I’m explaining how we can enable that feature, use it and how it will be helpful for filtering the required statements in … Continue Reading …[Read more]
I just recently used Event scheduler which was the major feature in MySQL 5.1 version. Its very much similar to the linux crontab functionality. MySQL Event is nothing but a bunch of statements which we can run on specific schedule. When you will create any event, its just a database object like table, view or … Continue Reading …[Read more]
This is the title of my first blog post on MySQL Performance Blog. It deals with a customer case where the customer was facing a peculiar problem where the rows column in the EXPLAIN output of the query was totally off. The actual number of rows was 18 times more than the number of rows reported by MySQL in the output of EXPLAIN. Now this can be a real pain as MySQL uses “the number of rows” estimation to pick and choose indexes and it could really be picking up a wrong index simply because of the wrong estimate. You...
Seeing as it looks like 5.5 is shortly about to go GA I thought I’d give it a run and see how well it works. The only way really to test it is to give it a bit of load and look for things which break. That I did with the 5.5.6-rc community rpms, compared to the 5.1 advanced rpms I usually run.
My colleagues, Ben and Peter, found a horrible problem which means that I can’t use this even for any real usage on my real servers. See: bug#57095 for all the gory details. Thanks to them both for finding the problem and then digging down and figuring out the real cause. Sometimes developers work a long way from the database so their errors don’t translate into something I can really look at in the database. They delved into the problem and then found the cause and a nice easy test case which I could report to MySQL.
After a couple of days of running this was …[Read more]
Recently while we were building a slave with a newer version of
MySQL 5.1 from an InnoDB Hot backup, the following error occurred
when we ran
mysql.time_zone OK mysql.time_zone_leap_second OK mysql.time_zone_name OK mysql.time_zone_transition OK mysql.time_zone_transition_type OK mysql.user OK Running 'mysql_fix_privilege_tables'... ERROR 13 (HY000) at line 311: Can't get stat of './mysql/general_log.CSV' (Errcode: 2) ERROR 13 (HY000) at line 316: Can't get stat of './mysql/slow_log.CSV' (Errcode: 2) FATAL ERROR: Upgrade failed
The problem is that in MySQL 5.1, it is possible to log the slow
query log and general log to tables in the
schema (source: Selecting General Query and Slow Query Log Output
Destinations). These tables are …
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