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Search Results for: stored functions

Renaming database schema in MySQL

One of the routine tasks for a DBA is renaming database schemas, and as such MySQL added a command to carry out that purpose called “RENAME DATABASE <database_name>”. However this command just made it through …

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utf8 data on latin1 tables: converting to utf8 without downtime or double encoding

Here’s a problem some or most of us have encountered. You have a latin1 table defined like below, and your application is storing utf8 data to the column on a latin1 connection. Obviously, double encoding …

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Innodb row size limitation

I recently worked on a customer case where at seemingly random times, inserts would fail with Innodb error 139. This is a rather simple problem, but due to it’s nature, it may only affect you …

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Flexviews – part 3 – improving query performance using materialized views

Combating “data drift” In my first post in this series, I described materialized views (MVs). An MV is essentially a cached result set at one point in time. The contents of the MV will become …

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Using Flexviews – part one, introduction to materialized views

If you know me, then you probably have heard of Flexviews. If not, then it might not be familiar to you. I’m giving a talk on it at the MySQL 2011 CE, and I figured …

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Percona Server 5.1.53-12.4

Percona Server version 5.1.53-12.4 is now available for download. It is now the current stable release version. Functionality Added or Changed  Percona Server 5.1.53-12.4 is based on MySQL 5.1.53.  New Features Added: Precompiled UDFs for Maatkit …

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Debugging problems with row based replication

MySQL 5.1 introduces row based binary logging. In fact, the default binary logging format in GA versions of MySQL 5.1 is ‘MIXED’ STATEMENT*;   The binlog_format  variable can still be changed per sessions which means …

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Using Gearman for Nightly Build and Test

by:

At Tokutek, Rich Prohaska used Gearman to automate our nightly build and test process for TokuDB for MySQL. Rich is busy working on TokuDB, so I’m writing up an overview of the build and test …

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MySQL Blob Compression performance benefits

When you’re storing text of significant size in the table it often makes sense to keep it compressed. Unfortunately MySQL does not provide compressed BLOB/TEXT columns (I would really love to have COMPRESSED attribute for …

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MVCC: Transaction IDs, Log Sequence numbers and Snapshots

MySQL Storage Engines implementing Multi Version Concurrency Control have several internal identifiers related to MVCC. I see a lot of people being confused what they are and why they are needed so I decided to …

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