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Displaying posts with tag: Oracle (reset)
Log Buffer #505: A Carnival of the Vanities for DBAs

This Log Buffer Edition searches through various blogs of Oracle, SQL Server and MySQL and picks a few contemporary ones.

Oracle:

Comma separated search and search with check-boxes in Oracle APEX

Once you have defined your users for your Express Cloud Service, all users with the role of Database Developer or higher can access the database Service Console.

Big Data Lite 4.7.0 is now available on OTN!

Install and configure Oracle HTTP Server Standalone

Can I …

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Group Replication: Shipped Too Early

This blog post is my overview of Group Replication technology.

With Oracle clearly entering the “open source high availability solutions” arena with the release of their brand new Group Replication solution, I believe it is time to review the quality of the first GA (production ready) release.

TL;DR: Having examined the technology, it is my conclusion that Oracle seems to have released the GA version of Group Replication too early. While the product is definitely “working prototype” quality, the release seems rushed and unfinished. I found a significant number of issues, and I would personally not recommend it for production use.

It is obvious that Oracle is trying hard to ship technology to compete with …

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Log Buffer #504: A Carnival of the Vanities for DBAs

This edition of Log Buffer covers Oracle, Microsoft SQL Server, and MySQL.

Oracle:

Data Pump or Data Pain Part02 – tablespace/user

Monday Spotlight: It’s About Security – Oracle Exadata SL6

0001_specify_date_format_mask.md copy

OGG Custom Adapters: How to include a unique identifier for …

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How does a relational database work

Introduction While doing my High-Performance Java Persistence training, I came to realize that it’s worth explaining how a relational database works, as otherwise, it is very difficult to grasp many transaction-related concepts like atomicity, durability, and checkpoints. In this post, I’m going to give a high-level explanation of how a relational database works internally while … Continue reading How does a relational database work →

MySQL Group Replication vs. Multi Source

In my previous post, we saw the usage of MySQL Group Replication (MGR) in single-primary mode. We know that Oracle does not recommends using MGR in multi-primary mode, but there is so much in the documentation and in presentations about MGR behavior in multi-primary, that I feel I should really give it a try, and especially compare this technology with the already existing multiple master solution introduced in 5.7: multi-source replication.

Installation

To this extent, I will set up two clusters using MySQL-Sandbox. The instructions for MGR in …

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Powerful MariaDB exports using MyMDBDump

You can export data from MariaDB using mysqldump and a bunch of other tools, but if you need really flexible output format, this might not be what you need. Instead, give MyMDBDump a try. This tool will export data just like mysqldump, but the output format is a lot more flexible. I urge you to test it and check out the documentation, but some if the features are, in short:

  • Dynamic column support - Dynamic columns can be exported as binary, JSON or even as SQL, where I think the latter is a pretty unique feature.
  • Oracle export format - This exports data as INSERT statements, just like mysqldump, but in an Oracle friendly way.
  • MS SQL / SQL Server format - This exports data as SQL Server friendly INSERTs.
  • Binary data formats - Supporting plain binary, base64, hex and a number of more formats.
  • Transaction support.
  • JSON export support - Including embedding dynamic columns …
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Percona Live Featured Tutorial with Øystein Grøvlen — How to Analyze and Tune MySQL Queries for Better Performance

Welcome to another post in the series of Percona Live featured tutorial speakers blogs! In these blogs, we’ll highlight some of the tutorial speakers that will be at this year’s Percona Live conference. We’ll also discuss how these tutorials can help you improve your database environment. Make sure to read to the end to get a special Percona Live 2017 registration bonus!

In this Percona Live featured tutorial, we’ll meet Øystein Grøvlen, Senior Principal Software Engineer at Oracle. His tutorial is on How to Analyze and Tune MySQL Queries for Better Performance. SQL query …

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MySQL Support Engineer's Chronicles, Issue #3

The original idea of this series was to publish one post per week, but it seems every other week I have some special topic that well deserves a dedicated post. Last week I had no time to complete my writing because of long (and, I hope, useful) Howto post on replacing corrupted partition using non-corrupted one from other server in replication setup. But I had links and notes collected in a draft that I am going to complete now.

First of all, during the previous week I had time to submit two more talks for the  …

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Install cx_Oracle for Python

This shows you how to install the cx_Oracle library for Python 2.7 on Fedora Linux. If Fedora has it on the server you can download it with the following yum command:

yum install -y cx_Oracle-5.2.1-11g-py27-1.x86_64.rpm

Currently, you’ll get the following failure because it’s not available in the Fedora repository:

Loaded plugins: langpacks, refresh-packagekit
mysql-connectors-community                                      | 2.5 kB  00:00:00     
mysql-tools-community                                           | 2.5 kB  00:00:00     
mysql56-community                                               | 2.5 kB  00:00:00     
pgdg93                                                          | 3.6 kB  00:00:00     
updates/20/x86_64/metalink                                      | 2.3 kB  00:00:00     
No package cx_Oracle-5.2.1-11g-py27-1.x86_64.rpm available.
Error: Nothing to do

You can download the …

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OTN appreciation day : MySQL 8.0 data dictionary

About one month ago, the MySQL team at Oracle released MySQL 8.0, with a large list of changes. One of the most interesting features in the new release is also one that does not show up much, also because the team has gone to great length to keep most of its implementation hidden: the data dictionary.

What makes the data dictionary so interesting, despite its scarce visibility, is the effect that it has on performance. Up to MySQL 5.7, searching the information_schema was an onerous operation, potentially crippling the system. In MySQL 8.0, the same operations are …

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