This third post in this series of blogs about MaxScale is finally
getting where you want to go: Install and configure MaxScale. The
first blog in this series was an overview of
what MaxScale is and the second about how to set up a Cluster of
MariaDB servers, using MariaDB Replication, for MaxScale to
access. But now it's time to introduce MaxScale.
If you skipped the second post as you already know how to set up
MariaDB with Replication and all that, be remineded that I will
use the same Linux server setup as outlined there even for the
MaxScale server and for a client to do some testing, and I
recommend you stick with that for now (for MariaDB itself you can
use any relevant setup you want, MaxSCale doesn't …
“Why can’t I find an MySQL DBAs or Developers?” This morning I got a message from a very perplexed Human Resources person on why their ads on Linkedin were not getting any results. Several such emails, calls, or messages make it to me each week and I would like take this opportunity to cover this subject. MySQL DBAs and Developers are out there but there are reasons why they are not interested in your job posting.
1. Provide details — “Exciting new position in rapidly growing start up in an expensive city and we want you to know how to program in every programming language, be a recent university graduate (hopefully PhD or higher), with ten years of experience but please be under twenty three years of age. Must prefer stock options and left over pizza crusts over a regular salary. And be flexible.” No, most ads are not quite that bad but several are very, very close.
…
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This is the second part of two series of blog posts to setup a
SSH connection on Windows from scratch. The first part can be
found here.
This article describes in step by step fashion a guide on
how to create and configure a SSH Tunnel with port forwarding to
a remote MySQL server running FreeSSHd on Windows using Putty
locally.
Today we upgraded the PCRE library bundled with MariaDB-10.0 to PCRE-8.34. This PCRE release includes some improvements, fixes for better stability and performance, and gives more compatibility with the Perl regular expressions.
I’d like to give details on the PCRE changes that especially affected MariaDB.
PCRE now includes support
for [[:<:]] and [[:>:]]
as used in the BSD POSIX library (written by Henry Spencer) to
mean “start of word” and “end of word“,
respectively. This is a good news for those project (like
MariaDB) migrating from the Henry Spencer’s library to PCRE, as
this non-standard syntax seemed to be used quite widely. Many
thanks to Philip Hazel and the PCRE team who kindly added this
extension into …
I want to give you tools that you can use for building databases that can handle complex relationships. In the previous article in this series, I looked at hierarchical data. The classic example of a hierarchy is an org chart. On most org charts I’ve seen, an employee has only one boss, which is a one-to-many relationship. The other kind of segmentation is many-to-many. A good instances of this is your social circle. Most people have many friends, and those friends have multiple friends themselves.
This is a common pattern. When developing a multi-tenanted application, users will often want to see and update information for multiple tenants. Imagine, if you will, a freelance Web developer. He’ll set up Google Analytics accounts for each client’s website, and he’ll add both the client and himself as users to the account. …
[Read more]MySQL provides commands to see the overall index size versus the data size.
One of them is “show table status” :
mysql> show table status like 't'\G
*************************** 1. row ***************************
Name: t
Engine: InnoDB
Version: 10
Row_format: Compact
Rows: 4186170
Avg_row_length: 34
Data_length: 143310848
Max_data_length: 0
Index_length: 146030592
Data_free: 6291456
Auto_increment: NULL
Create_time: 2014-02-04 15:40:54
Update_time: NULL
Check_time: NULL
Collation: latin1_swedish_ci
Checksum: NULL
Create_options:
Comment:
1 row in set (0.00 sec)
So here, we have these “estimations”, run ANALYZE TABLE before to get more accurate estimates :
Data_length: 143310848, 136Mb clustered index size.
Index_length: 146030592, 139Mb secondary index size.
In this example, I have …
[Read more]ClusterControl for Percona XtraDB Cluster is now available in three different versions thanks to our partnership with Severalnines. ClusterControl will make it simpler to manage and monitor Percona XtraDB Cluster, MySQL Cluster, MySQL Replication, or MySQL Galera.
I am very excited about our GA release of Percona XtraDB Cluster 5.6 last week. As Vadim described in his blog post announcing the release, we have brought together the benefits of Percona Server 5.6, Percona XtraBackup and Galera 3 to create a drop-in compatible, open source, state-of-the-art high availability MySQL clustering solution. We could not have done it without the close cooperation and help of our partners at Codership. To learn more, join us on February …
[Read more]February 4, 2014 By Severalnines
Great news for Percona customers! We are thrilled to announce our partnership with Percona. Effective immediately, Percona customers will be able to enjoy the advanced automation, monitoring and cluster management capabilities of ClusterControl. Percona will be bundling, with its Cluster support contracts, Percona ClusterControl - a privately branded version of ClusterControl Community. Together we're providing support for the full stack, from Percona XtraDB Cluster to management tools, giving customers one number to call.
For anyone who has deployed, managed or monitored a mission-critical database cluster, you will know that having the right tools can really make a difference. This is exactly our goal with ClusterControl, with a focus on operational management from day one. In only a few clicks, ClusterControl provides customers the ability to deploy Galera-based MySQL Clusters in private …
[Read more]This continues on from my post yesterday and also contains content from my linux.conf.au 2014 talk (view video here).
Way back in May in the year 2000, a feature was added to MySQL that would keep many people employed for many years – replication. In 3.23.15 you could replicate from one MySQL instance to another. This is commonly cited as the results of two weeks of work by one developer. The idea is simple: create a log of all the SQL queries that modify the database and then replay them on a slave. Remember, this is before there was concurrency and everything was ISAM or MyISAM, so this worked (for certain definitions of worked).
…
[Read more]I recently blogged about tracking metadata locks in the latest MySQL, and now I want to discuss how to track these metadata locks in MariaDB.
In MySQL 5.7, there is a table named `metadata_locks` added to the performance_schema (performance_schema must be enabled *and* the metadata_locks instrument must be specifically enabled as well.
In the MariaDB 10.0 implementation (as of 10.0.7), there is a table named METADATA_LOCK_INFO added to the *information_schema*. This is a new plugin, so the plugin must be installed, but that is very simple with:
INSTALL SONAME 'metadata_lock_info';
Then, you will have the table.
To see it in action:
Connection #1:
mysql> create table t (id int) engine=myisam; mysql> begin; mysql> select * from t;
Connection #2:
mysql> alter table t add index …[Read more]