Below video will depict :
* How to set a login path
* How to use login path in mysql client
* How to use login path in mysqldump
* How to remove login path
You can download the slides from below URL
Below video will depict :
* How to set a login path
* How to use login path in mysql client
* How to use login path in mysqldump
* How to remove login path
You can download the slides from below URL
Having big tables is one of the expected database problems, especially, for the fast growing database systems. In fact, big tables itself is not a problem but with big tables, the following problems are strongly expected:
All the above problems will show up the need for scaling! So, let’s check out what are the possible solutions for that problem:
On a recent engagement I worked with a customer who makes extensive use of UUID() values for their Primary Key and stores it as char(36), and their row count on this example table has grown to over 1 billion rows.
The table is INSERT-only (no UPDATEs or DELETEs), and the bulk of their retrieval are PK lookups. Lookups by PK were performing acceptably, but they were concerned with the space usage by the table as we were approaching 1TB (running with innodb_file_per_table=1 and Percona Server 5.5).
This schema model presents an increasing burden for backups since they use Percona XtraBackup, and so the question was asked: does their choice of an effectively random Primary Key based on UUID() impact their on-disk storage, and to what extent? And as a neat trick I show towards the end of this post how you can calculate the …
[Read more]The Ubuntu 12.04.3 LTS release only provides MySQL 5.1 and MySQL 5.5 using the default Ubuntu package manager.
Oracle (owners of the MySQL(tm)) now provide Debian/Ubuntu APT repositories for all GA and DMR versions of MySQL including supporting Ubuntu 12.04.
The following steps demonstrate upgrading from the Ubuntu 5.5 server package to the Oracle 5.6 server package.
Verify MySQL Packages
$ apt-cache search mysql-server mysql-server - MySQL database server (metapackage depending on the latest version) mysql-server-5.5 - MySQL database server binaries and system database setup mysql-server-core-5.5 - MySQL database server binaries auth2db - Powerful and eye-candy IDS logger, log viewer and alert generator cacti - Frontend to rrdtool for monitoring systems and services torrentflux - web based, feature-rich BitTorrent download manager
Verify …
[Read more]As part of a MySQL 5.5 to MySQL 5.6 upgrade across several Ubuntu servers of varying distros an audit highlighted a trivial but interesting versioning identification error in Ubuntu’s packaging of MySQL.
Ubuntu 12.04 LTS
$ sudo dpkg -l | grep mysql-server-5.5 ii mysql-server-5.5 5.5.41-0ubuntu0.12.04.1 ...
$ mysql -uroot -p -e "SELECT VERSION()" +-------------------------+ | VERSION() | +-------------------------+ | 5.5.41-0ubuntu0.12.04.1 | +-------------------------+
But when you look at the mysql --version it does NOT
say 5.5.41.
$ mysql --version mysql Ver 14.14 Distrib 5.5.34, for debian-linux-gnu (x86_64) using readline 6.2
Ubuntu 14.04 LTS
On 14.04 I get expected results.
$ sudo dpkg -l | grep mysql-server-5.5 ii mysql-server-5.5 5.5.41-0ubuntu0.14.04.1 ...
rbradfor@rubble:~$ mysql -uroot -p -e "SELECT VERSION()" …[Read more]
MySQL 5.6 will now automatically recreate the InnoDB redo log
files during a MySQL restart if the size (or number) of these
logs changes, i.e. a change to innodb_log_file_size.
See Changing the Number or Size of InnoDB Log
Files which states “If InnoDB detects that the
innodb_log_file_size differs from the redo log file size, it will
write a log checkpoint, close and remove the old log files,
create new log files at the requested size, and open the new log
files.”
Before MySQL 5.6 it was necessary to stop MySQL and remove the InnoDB log files manually before restarting MySQL.
The error log shows:
tail -f /mysql/log/error.log ... 2015-03-28 21:51:25 3767 [Warning] InnoDB: Resizing redo log from 2*3072 to 2*65536 pages, LSN=1626017 2015-03-28 21:51:25 3767 [Warning] InnoDB: Starting to delete and …[Read more]
Mermaids have the same probability of fixing
your permission problems, but people continue believing in the
FLUSH PRIVILEGES myth.I see suggesting the usage of FLUSH
PRIVILEGES every time someone writes a tutorial or a
solution to a problem regarding creating a new account or
providing different privileges. For example, the top post on
/r/mysql
as of the writing of these lines, “MySQL:The user specified as a definer does not
exist (error 1449)-Solutions” has multiple guilty cases of
this (Update: the user has corrected those lines
after I posted this article).
It is not my intention to bash that post, but I have seen …
[Read more]Check Out Our Latest Technical Resources for MySQL, MariaDB, Postgres and MongoDB.
This blog is packed with all the latest resources and tools we’ve recently published! Please do check it out and let us know if you have any comments or feedback.
New Technical Live Webinar
Join our colleague Krzysztof Książek for a deep-dive session what to monitor in Galera Cluster for MySQL & MariaDB. Krzysztof is a MySQL DBA with experience managing complex database environments for companies like Zendesk, …
[Read more]Can we output content of a mariaDB table into JSON using the CONNECT Storage Engine ? MariaDB and MySQL are not currently JSON friendly databases. The usage of JSON in MySQL is almost inexistent with the excetion of the explain JSON output and of MariaDB dynamic column dump. There also exist a few udf (in [...]
Years ago when I worked for the MySQL Support organization at the original MySQL AB, we spoke about MySQL Support as insurance and focused on a value proposition similar to that of car insurance. For your car to be fully covered, you must purchase car insurance before the incident happens – in fact most places around the world require automobile insurance. Similarly with many organizations, any production-use technology might be mandated to have its own insurance in the way of 24/7 support.
I think however this is a very one-sided view that does not capture the full value (and ROI) that a MySQL Support contract with Percona provides. Let’s look at the different dimensions of value it provides based on the different support cases we have received throughout the years.
Reduce and Prevent …
[Read more]