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The latest from the MySQL community

Ideas, releases, practical guides, and perspectives from the people building with MySQL.

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MySQL Datamasking using ProxySQL – part 2

First of all I want to say thanks to Thomas that sent me feedback on part1 (see his comment). And indeed all three cases were able to defeat the datamasking.

I rewrote then the rules to also take those cases in consideration:

ProxySQL> DELETE FROM mysql_query_rules where rule_id  INSERT INTO mysql_query_rules 
          (rule_id,active,username,match_pattern,replace_pattern,apply)  
          VALUES (1,1,'devel','`cc_num`',"cc_num",0);
ProxySQL> INSERT INTO mysql_query_rules 
          (rule_id,active,username,match_pattern,replace_pattern,apply)  
           VALUES (2,1,'devel','^[sS][eE][lL][eE][cC][tT] (.*)cc_num([ ,\n])(.*)',
           "SELECT \1CONCAT(LEFT(cc_num,2),REPEAT('X',10)) cc_num\2\3",1);


However the current recursive implementation of ProxySQL (using flagIN & flagOUT) is not an option to face the case where a …

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MySQL 5.7 and administration

MySQL 5.7 improved as compare to previous releases in terms of transnational capabilities, performance with high load, high Availability, Security and it’s defaults.

Check my blog post : MySQL 5.7 features

This blog post will describe End to End implementation of MySQL on Linux distributions Which will cover MySQL Installation, configuration and administration in production environment with proper configuration. So you can start using your application by implementing following setup and in future you can change it if requires.

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MySQL Group Replication OOW Tutorial

Download Slides The second MySQL tutorial session at Oracle Open World was “MySQL Group Replication in a Nutshell” by MySQL Community Manager Frederic Descamps. This is succinctly described as: “Multi-master update anywhere replication for MySQL with built-in conflict detection and resolution, automatic distributed recovery, and group membership.

Percona XtraDB Cluster 5.6.32-25.17 is now available

Percona announces the new release of Percona XtraDB Cluster 5.6.32-25.17 on October 4, 2016. Binaries are available from the downloads area or our software repositories.

Percona XtraDB Cluster 5.6.32-25.17 is now the current release, based on the following:

  • Percona Server 5.6.32-78.1
  • Galera Replication library 3.17
  • Codership wsrep API version 25

Bugs Fixed:

  • Fixed DONOR …
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Using the super_read_only system variable

This blog post will discuss how to use the MySQL super_read_only system variable.

It is well known that replica servers in a master/slave configuration, to avoid breaking replication due to duplicate keys, missing rows or other similar issues, should not receive write queries. It’s a good practice to set

read_only=1

 on slave servers to prevent any (accidental) writes. Servers acting as replicas will NOT be in read-only mode automatically by default.

Sadly, 

read_only

 has an historical issue: users with the SUPER privilege can override the setting and could still run DML queries. Since Percona Server 5.6.21 and MySQL 5.7.8, however, you can use the

super_read_only

 feature to extend the

read_only
…[Read more]
Cost-based Optimization in MySQL 5.7

Optimiser is the brain of the RDBMS. Optimiser decides the right access method , algorithms , join order and right index to be used for better execution of the query. This blog is made to shed some lights on Cost based optimiser in MySQL 5.7. The cost or statistics are stored in the data dictionary .

What is cost-based optimization ?

  • The cost model is based on estimates of cost various operations occur during query execution.
  • The optimizer has a set of default “cost constants” it will make decision on execution plans.
  • In MySQL 5.7, the optimizer has addition a database of cost estimates to use during the execution plan.
  • These cost estimates are stored in server_cost & engine_cost tables in MySQL schema. For more details Cost Model

MySQL …

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Database Security - MySQL Upgrade Instructions for Zero-day Exploit

You must have heard about the CVE-2016-6662, the recent zero-day exploit exposed in most of MySQL and its variants. The vulnerability flaw can be exploited by a remote attacker to inject malicious settings into your my.cnf,. you can read about the details here.

At the moment, all supported MySQL vendors by ClusterControl (Oracle, Codership, Percona, MariaDB) have been patched with a bug fix and released in their respective package repository:

Vendor Software Patched Release
Oracle MySQL Server 5.5.52
5.6.33
5.7.15
Percona Percona Server
Percona XtraDB …
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PerconaLive Amsterdam 2016 - Talks and shows

With Oracle Open World behind us, we are now getting ready for the next big event, i.e. the European edition of PerconaLive. I am going to be a presenter three times:

  • MySQL operations in Docker is a three-hour tutorial, and it will be an expansion of the talk by the same title presented at OOW. Attendees who want to play along can do it, by coming prepared with Docker 1.11 or later and the following images already pulled (images with [+] are mandatory, while [-] are optional):

      …
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Showing the hidden tables in MySQL 8 data dictionary

The freshly released MySQL 8.0 includes a data dictionary, which makes MySQL much more reliable. Thanks to this features, we don't have any '.frm' files, and querying the information_schema is 30x to 100x faster than previous versions.

One drawback of the implementation is that the data dictionary tables are hidden by design.

While the reason is fully understandable (they don't want to commit on an interface that may change in the future) many curious users are disappointed, because openness is the basis of good understanding and feedback.

The problem to access the dictionary tables can be split in three parts:

  • Finding the list of tables; …
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Introducing BakaSQL, the MySQL web-based sandbox for query execution

BakaSQL: a bit of history When I joined this new company I was already aware there was a lot of work to do. There was no DBA Team to speak of; any MySQL related task was handled by the sysadmins, and the company was growing as fast as you can imagine, with 15-20 new employees arriving each month, most of them in the IT department. For sure, there was much fun ahead.

During my first week in the new job  I immediately felt that something was not right. I was receiving too much DMLs to execute each day, spanning a wide set of servers, schemas an tables. This is not something I had seen before, so I started asking around what the reason behind it was.  It turned out that there were multiple reasons behind it:

  • there were known bugs in the applications that were never fixed
  • application configuration items were stored in MySQL, but there was no admin panel to modify them
  • …
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