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Showing entries 1 to 10 of 33116 10 Older Entries
Three wishes for a new year
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Another new year by Jewish calendar. What do I wish for the following year?

  • World peace
  • Good health to all
  • Multi-core execution for queries
  • After having evaluated a few columnar databases, and having seen how a single query gets 24 cores busy, I can't look at MySQL the same way again. The fact that a single query consumes a single core only doesn't seem right in the year 2014. Shard-query is a cool application-level attempt to solve the above; I would like to see stuff like this implemented inside the server (or inside the storage engine where possible).

    None of my wishes in previous years [2010], [2011],

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    Changing the DEFINER of MySQL stored routines etc.
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    Mon, 2014-09-22 12:19hartmut

    The question seemed easy enough:

    We've dropped a user, now we want to change the DEFINER on all database objects that currently have it set to this dropped user?

    This should be possible by checking the INFORMATION_SCHEMA tables of the appropriate object types (routines, triggers, views and events) and performing an ALTER on each of them that just modifies the DEFINER but nothing else, right?

    Unfortunately it isn't that easy, or at least not yet (see and ).

    Events are closest to this as ALTER EVENT does support changing the definer, but it also

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    PagerDuty Incident Alerting for ClusterControl
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    September 22, 2014 By Severalnines

    Need to add phone and SMS alerting to ClusterControl? ClusterControl 1.2.8 introduces support for PagerDuty, an alerting service for Ops teams to schedule on-calls and add phone and SMS notifications to IT tools. By integrating PagerDuty with ClusterControl, you can start receiving phone, SMS and email notifications for all important database events as monitored by ClusterControl. Alerts go directly to the right person who can solve the issue.

    This integration is possible thanks to a new plugin interface, that takes ClusterControl alarms in JSON format and outputs to an external system via plugins. Plugins can be either scripts or

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    How to start Percona Xtradb Cluster on CentOS 7
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    Normally, when we want to start PXC (Percona XtraDB Cluster) on RHEL/CentOS 6 or older then that, we can simply start with init.d script or service command. i.e shell> /etc/init.d/mysql start OR shell> /etc/init.d/mysql bootstrap-pxc shell> service mysql start. But, Continue reading →   [Read more...]
    Using Netlink to Optimize Socket Statistics
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    This is a story of using low-level kernel interfaces to optimize an edge case one of our agents encountered in some servers. The TL;DR version is that accessing /proc/ can be very expensive if there are a lot of network connections, and the Netlink interface between userspace and kernel space is a much more efficient method.


    VividCortex runs several agents, each specialized to a set of tasks. There’s one for gathering operating system metrics, called vc-os-metrics. We capture per-process metrics in the same high resolution as all of our metrics, because in many cases a performance problem is due to a process causing collateral damage to another process by hogging resources. In addition to per-process metrics, we gather a lot of other

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    MySQL Notifier 1.1
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    MySQL Notifier 1.1 (1.1.6 GA, published on Monday, 22 Sep 2014)
    MySQL for Excel 1.3
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    MySQL for Excel 1.3 (1.3.2 GA, published on Monday, 22 Sep 2014)
    Downgrading from MySQL 5.6 to MySQL 5.5
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    Last week I had to downgrade from MySQL 5.6 to 5.5. The reason for this was that the application used a very old Connector/J and that's incompatible with MySQL 5.6 because the removal of SET OPTION syntax.

    We're now planning to upgrade Connector/J to be able to upgrade to 5.6 again.

    There are two methods of downgrading:
    • Dump/Restore with mysqldump. This is easy and reliable, but can take more time.
    • In place (replace binaries, don't change data). This fast, but won't work if file formats have changed.
    As expected this is documented in the MySQL Reference Manual.

    I went for the in place method. I expected this to work without many issues as this database was not using the fancy new features like fulltext indexes for

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    CIS Oracle MySQL 5.6 Security Benchmark
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    I've been working on the CIS security benchmark for Oracle MySQL 5.6. There already is a benchmark document for earlier versions of MySQL.

    The benchmark document helps you to ensure you have a secure configuration for MySQL.

    Center for Internet Security (CIS) is a nonprofit organization.

    The Call For Participation is now open.

    If you are already a CIS member then you can download the document here. If you don't have an account you can register for free.
    What part of NoSQL don't you understand?
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    In the word "NoSQL", the letters "No" are an acronym so the meaning is "Not Only SQL" rather than "No SQL". True or false?

    Historically, it's false

    The first NoSQL product was a classic DBMS which didn't happen to use SQL for a query language, featured in Linux Journal in 1999. Its current web page has a traffic-sign symbol of the word SQL with a bar through it, and a title "NoSQL: a non-SQL RDBMS".

    For a meetup in June 2009 about "open source, distributed, non-relational databases" the question came up "What's a good name?" Eric Evans of Rackspace suggested NoSQL, a suggestion which

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    Showing entries 1 to 10 of 33116 10 Older Entries

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