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Send messages between sessions on MySQL or MariaDB
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Suppose you want to send a message from one SQL session to one or more other sessions, like "Hey, session#13, here is the latest figure for your calculation, please acknowledge". I'll say what Oracle and EnterpriseDB and DB2 do, then rate the various ways to implement something similar in MySQL and MariaDB, and finish with a demo of the procedure that we use, which is available as part of an open-source package.

The syntax was established by Oracle, with EnterpriseDB and IBM following suit. The details are in the Oracle 12c manual and the …

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Log Buffer #444: A Carnival of the Vanities for DBAs
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This Log Buffer Edition covers some blog posts of Oracle, SQL Server and MySQL from this past week.


  • Oracle Utilities Application Framework V4. includes a new help engine and changes to the organization of help.
  • Very simple oracle package for HTTPS and HTTP.
  • Oracle ZFS Storage Appliance surpasses $1B in Revenue (Oct …

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Employee_Team +0 Vote Up -0Vote Down

mysql < quarto.sql

Example game play:

mysql> -- Start the game and pass the first piece in the lower nibble
mysql> CALL SetupGame(0x0A);
| rules                                                                |
| Quarto: 4 in a line (row, column, or long diagonal) with at least one bit in common wins.
CALL Play(move); -- high 4 bits are board position, low 4 bits are piece for next player
CALL PrintBoard(base); -- to display the board. Useful bases are 16 and …
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Online DDL and Percona XtraDB Cluster 5.6
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I presented a talk at Percona Live Amsterdam a few weeks ago (simple recipes for your Galera cluster), and one of the topics was schema changes. I discussed the drawbacks and benefits of Total Order Isolation (TOI), …

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When mysqld kills mysqld
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The other day a colleague and friend of mine, Peter Boros, had a case where one of our clients had to track down the process shutting down MySQL. This blog is based on the discussion we had about that internally.

Our client wanted Peter to identify the culprit behind periodic shutdowns. This proved to be slightly more difficult than usual, for reasons that you might guess from the title of this blog.

Here is what Peter saw in the logs:

150928 15:15:33 [Note] /usr/sbin/mysqld: Normal shutdown
150928 15:15:36 [Note] Event Scheduler: …
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Simplifying Docker Interactions with BASH Aliases
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Docker has been consuming my life in the last few weeks. I have half a dozen projects in progress that use containers in some fashion, including my Visualizing MySQL’s Performance Schema project.

Since I prefer to work from a Mac laptop, I have to utilize a Linux Virtual Machine (VM) which runs the Docker daemon. Luckily, Docker Machine makes this a very simple …

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Getting started MySQL Group Replication on Ubuntu with MySQL Sandbox
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Welcome to next topic dedicated to Group Replication plugin. Today’s topic is to get started with Group Replication. As you remember we set up our environment using MySQL Sandbox on Ubuntu 14.04 and also we have compiled plugin with MySQL 5.7.8-rc on Ubuntu 14.04. Please refer to this topics respectively:

  1. MySQL Sandbox creating test environment
  2. Compiling MySQL …
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MySQL lost “AUTO_INCREMENT” after a long time
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I create a empty table and then alter this table's "AUTO_INCREMENT" starts from 10000000.After a long time ,MySQL lost "AUTO_INCREMENT" definition when I show this table again. MariaDB has the same problem but Percona Server is fine.


Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 141028725
Server version: 5.6.17-log MySQL Community Server (GPL)

Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights …
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New statements I'd like to see in MySQL 5.8
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Following up on New features I'd like to see in MySQL 5.8, here are statements I would like to see in MySQL 5.8:

    When promoting a slave to master, I want to be able to enable all those events that are in SLAVESIDE_DISABLED state. Today I script an iteration over the events an constructing the ALTER EVENT...ENABLE statement one by one. Just activate those!
    I have a …

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Sound advice for GTID, with caveats
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During the PerconaLive conference in Amsterdam, I attended a session where I heard a good piece of advice about using GTID. It amounts to: look at SHOW SLAVE STATUS output, and if you see more than one line in the Executed_Gtid_Set field, this tells you immediately if someone has written on a slave database.
This is good advice. Let's dissect it. Here is what a regular slave looks like, when nobody has messed up with it:

*************************** 1. row ***************************

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Showing entries 1 to 10 of 35157 10 Older Entries

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