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Showing entries 1 to 10 of 33483 10 Older Entries
Percona Server 5.6.21-70.1 is now available
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Percona is glad to announce the release of Percona Server 5.6.21-70.1 on November 24, 2014. Download the latest version from the Percona web site or from the Percona Software Repositories.

Based on …

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Log Buffer #398, A Carnival of the Vanities for DBAs
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This Log Buffer Edition covers some informative and interesting posts from Oracle, SQL Server and the MySQL.

Oracle:

If you’re not using Toad DBA Suite, it’s sometimes hard to find solutions. Somebody wanted to know how to find indexes that aren’t that aren’t indirect. Indirect indexes are those created for a primary key because a primary key column or set of columns are both not null and uniquely constrained. You can’t drop a unique index for a primary key without dropping the primary key constraint that …

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Schema changes in MySQL for OpenStack Trove users
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People using OpenStack Trove instances can hit a common issue in the MySQL world: how to perform schema change operations while minimizing the impact on the database server? Let’s explore the options that can allow online schema changes.

Summary

With MySQL 5.5, pt-online-schema-change from Percona Toolkit is your best option for large tables while regular ALTER TABLE statements are only acceptable for small tables. Also beware of metadata locks.

With MySQL 5.6, almost all types of …

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Creating JSON documents with MariaDB
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You probably know about two MariaDB great features: Dynamic Columns and Virtual Colums. I don’t think that we already found all possible use cases for them: more ideas will come in the future, and hopefully someone will write about them. Here, I will describe a use case which involves both Virtual Columns and Dynamic Columns.

Now, suppose that we have relational data in MariaDB, and we want to …

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Geographic replication with MySQL and Galera
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Introduction

With the introduction of Galera replication for MySQL, Codership has, in my opinion, provide the most significant support to MySQL that the community had seen in the last tree years.

Codership had filled a significant gap in MySQL replication capability, succeeding in a task where many before had failed.

Not only Codership is constantly committed in doing their solution better and more solid, and they are the most friendly and helpful team I have met in years.

In short chapeau to all of the guys! Great job, I am really proud to have the opportunity to discuss, interact with …

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Aurora for MySQL is coming
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I am excited about Aurora for MySQL. While there aren't many details, I have two conclusions from the information that is available. First, many talented people did great work on this. Second, many customers want the features it provides and some of these features are otherwise unavailable unless you are web-scale and can afford a team of automation experts. This is a big deal and good for the MySQL community. I am not just writing this to boost my priority on the Aurora preview signup list.

I don't think it matters whether Aurora has better performance. The big story is …

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Sys Schema for MySQL 5.6 and MySQL 5.7
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Performance Schema (P_S) has been available since MySQL 5.5, more than 4 years ago. It is still difficult to see production servers with P_S enabled, even with MySQL 5.6 where the feature is enabled by default. There have been several complaints like the overhead, that the fix is a work in progress, and the ease of use. 52 tables to query and 31 configuration variables is enough to scare people.

There is a solution for the second problem, the usability. It’s name is “sys schema“. It is a collection of views, functions and procedures to make P_S more user friendly.

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Logging with MySQL: Error-Logging to Syslog & EventLog
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You’ve already read it in What’s new in 5.7 (So Far) — the MySQL server now has new-and-improved supported for syslog (on unix-like systems) and EventLog (on Windows). In the next few paragraphs, we’ll take a look at what they are, what has changed, and how they can make your life easier.

The MySQL server supplies information in two main ways:

  1. The client will receive a reply to every statement. If everything goes right, then we’ll see a simple OK for success, or a result set for SELECT, SHOW, etc.; and …
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Multi-source Replication with Galera Cluster for MySQL
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November 20, 2014 By Severalnines

Multi-source replication means that one server can have multiple masters from which it replicates. Why multi-source? One good reason is to consolidate databases (e.g. merge your shards) for analytical reporting or as a centralized backup server. MariaDB 10 already has this feature, and MySQL 5.7 will also support it. 

It is possible to set up your Galera Cluster as an aggregator of your masters in a multi-source replication setup, we’ll walk you through the steps in this blog. Note that the howto is for Galera Cluster for MySQL (Codership) and Percona XtraDB Cluster. In a separate post, …

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Improving InnoDB index statistics
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The MySQL/MariaDB optimiser likes to know things like the cardinality of an index – that is, the number of distinct values the index holds. For a PRIMARY KEY, which only has unique values, the number is the same as the number of rows.  For an indexed column that is boolean (such as yes/no) the cardinality would be 2.

There’s more to it than that, but the point is that the optimiser needs some statistics from indexes in order to try and make somewhat sane decisions about which index to use for a particular query. The statistics also need to be updated when a significant number of rows have been added, deleted, or modified.

In MyISAM, …

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Showing entries 1 to 10 of 33483 10 Older Entries

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