The default sharding key is still the primary key!

To see that 7.5.4 does not behave as hidden pk case in 7.2.26, look also in the other columns of explain output. The partitions column should be ignored for NDB tables.

Still, you found a bug. The explain output should not depend on how partitioning is specified as long as it is the same.

For NDB the partition pruning is actually not done by the optimizer in MySQL server but within NDB itself.

To inspect the table definition used within NDB one can use ‘ndb_desc -d shard_check_pk’ it should reveal that there are no extra hidden columns, and also that the sharding key called distribution key in NDB is the same as the primary key.

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Helsinki, Finland & London, UK  – January 9th 2017 – Codership, whose Galera Cluster technology brings high availability (HA) and scalability to open source databases worldwide, has seen its technology break the one million download barrier. Codership’s customer roster has grown over 100 percent thanks to the adoption of OpenStack by enterprises and the recent strategic partnership with MariaDB.

Galera has been recognised as the most widely used OpenStack High Availability technology for the second year in a row. According to the OpenStack Survey 2016, one-third of users rely on Galera Clusters running on MariaDB and MySQL.

To cope with an increase of customer demand coming from various industries such as financial services, retail and telecoms, Codership has grown its engineering hires by 50 percent. The new team members will ensure Galera continues to deliver on its mission to protect …

This one is for all MySQL-DBA's, which are working on macOS. Since the Apple OS has a rather peculiar way of starting and stopping MySQL, compared to Linux, you can run into some issues. These problems occur especially, if you have no access to the GUI.

Preparation

Put skip-grant-tables into the mysqld section of the my.cnf. A my.cnf can be found in /usr/local/mysql/support-files. You MUST work as root for all the following steps.

shell> sudo -s
shell> vi /usr/local/mysql/support-files/my-default.cnf

...
[mysqld]
skip-grant-tables
skip-networking
...

Save the configuration file! (In vi this is "[ESC] + :x")

Continue with stopping MySQL:

launchctl unload /Library/LaunchDaemons/com.oracle.oss.mysql.mysqld.plist

Restart MySQL, so skip-grant-tables becomes active:

launchctl load …

MySQL Cluster does an automatic sharding/partitioning to the tables across data nodes, enabling databases to scale horizontally to serve read and write-intensive workloads, but what is the default sharding key used in partitioning the data?
According to the recent update (Oct, 2016) of the MySQL Cluster white paper, primary key is the default sharding key:

By default, sharding is based on hashing of the primary key, which generally leads to a more even distribution of data and queries across the cluster than alternative approaches such as range partitioning.

However, that is not the case in all MySQL Cluster versions so far!
In this post, I’ll do some test cases on MySQL Cluster (of 4 datanodes) to confirm the default sharding key.

Testing on MySQL Cluster 7.2.26 …

The innodb_buffer_pool_size the most important variable for entire MySQL server. Last few years, you have seen the drastic improvements in the InnoDB storage engine features. After Oracle acquiring the MySQL, the importance of InnoDB storage engine grows multiple times over MyISAM. Even though MySQL supports multiple pluggable storage engines, one of the main reasons is its ACID compliance properties. Recent improvements in the MySQL 5.7 such as online innodb_buffer_pool_size configuration made it as a highly flexible and allow us to get the best performance without long downtime.
Initially, when I start to configure the innodb_buffer_pool_size variable on my test environment, like most of us, I googled as, 
What is MySQL innodb_buffer_pool_size?Do I need to change MySQL innodb_buffer_pool_size?What are the recommendations for innodb_buffer_pool_size in MySQL?What are the best practices for configuring innodb_buffer_pool_size …

If we work in big application or project of Laravel Framework sometimes we require to manage column value into comma separated because we can save memory of database But if we store comma separated value in column with ids then its difficult to inner join or left join and get records from another

If we work in big application or project of Laravel Framework sometimes we require to manage column value into comma separated because we can save memory of database But if we store comma separated value in column with ids then its difficult to inner join or left join and get records from another

Amazon is releasing new products & services to it’s global cloud compute network at a rate that has all of our heads spinning. Join 32,000 others and follow Sean Hull on twitter @hullsean. Here’s new stuff worth mentioning around databases & data. 1. For ETL – AWS GLUE Moving data from your transactional MySQL or … Continue reading What products & improvements are new on AWS? →

Most users of MySQL utilize the mysqldump utility to backup their database. While mysqldump is handy and easy-to-use (and free), if you have data which is important to your business, then you should take a look at the MySQL Enterprise Edition – and use MySQL Enterprise Backup instead. The MySQL Enterprise Backup allows you to backup your database without the table locking you get with mysqldump. And, it is extremely fast – especially when you have to restore your database. Here is a sample speed comparison between MySQL Enterprise Backup and …

This post discusses archiving MySQL and MongoDB data, and determining what, when and how to archive data.

Many people store infrequently used data. This data is taking up storage space and might make your database slower than it could be. Archiving data can be a huge benefit, both regarding the performance impact and storage savings.

Why archive?

One of the reasons for archiving data is freeing up space on your database volumes. You can store archived data on slower, less expensive storage devices, and current data on the faster database drives. Archiving old data makes backups and restores run faster since they need to process less data. Last, but by no means least, archiving data has the benefit of making your queries perform more efficiently since they do not need to process through old …