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Why I think SQL_MODE is useless...

I think the SQL_MODE setting is a sort-of good idea, but that the implementation of it is useless, more or less. What I would want from a feature like this is to allow me to control the quality of the data in the database, but that is not what SQL_MODE does, regrettably.

Rather, what SQL_MODE does is define a default quality checking level for an individual session. This is NOT the same thing as guaranteeing that data has certain qualities in the database.

  1. To begin with, a specific session can change it. If you want to insert an invalid data, just set SQL_MODE=ALLOW_INVALID_DATES and go ahead and insert.
  2. Secondly, setting this to a non-default value requires no specific privileges at all!
  3. Thirdly, as anyone can bypass these checks, you would assume that there was a way to check afterwards that data follows a specific SQL_MODE, or at least a function that I could apply to a table or column …
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Communication protocols in MySQL

Generally, MySQL supports connections between clients and the server using several networking protocols. Below are the main protocols which are used by client to connect with MySQL server. TCP/IP Unix socket file Named pipe Shared memory TCP/IP connections are supported by any MySQL server unless the server is started with the –skip-networking option. These connections … Continue Reading

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How to use object types?

A tale of Oracle SQL object types, their constructors, and how you use them. This demonstrates what you can and can’t do and gives brief explanations about why.

The following creates a base SAMPLE_OBJECT data type and a sample_table
collection of the base SAMPLE_OBJECT data type.

CREATE OR REPLACE TYPE sample_object IS OBJECT
(id       NUMBER
,name     VARCHAR2(30));
/
 
CREATE OR REPLACE TYPE sample_table IS TABLE OF sample_object;
/

If the base SAMPLE_OBJECT data type were a Java object, the default constructor of an empty call parameter list would allow you to construct an instance variable. This doesn’t work for an Oracle object type because the default constructor is a formal parameter list of the object attributes in the positional order of their appearance in the declaration statement.

The test case on this concept is:

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MySQL Cluster 7.2 GA Released, Delivers 1 BILLION Queries per Minute

Oracle is delighted to announce the immediate availability of the production-ready, GA release of MySQL Cluster 7.2, available for download under the GPL, and as part of the commercial MySQL Cluster Carrier Grade Edition, including management tools, product certifications and 24x7 global support.

New benchmarks demonstrate MySQL Cluster's ability to support the most demanding web and telecoms workloads, while maintaining 99.999% availability. MySQL Cluster delivered 1 billion queries per minute (17.6 million queries per second), scaled-out across 8 x commodity Intel x86 server nodes, accessed by the NoSQL C++ NDB API.

Summary Tables with MySQL

I was recently talking with a few people and the concept of summary tables came up as solutions for them. The issue is, they never thought of it. Hopefully this post will help them as well as others.
Summary Tables are not a new concept. They are exactly what they sound like, basically summary of existing data. Aggregated tables, materialized views and summary tables are very dominate in data warehouses. You can also take advantage of these concepts as part of your reporting systems as well.
So summary tables are real tables. So you can take advantage of indexes and etc with them. In the examples I am using, I consider them more of a summary table than aggregated tables . Depending on your application and needs it could grow into more of an aggregated tables and or materialized views situation.
How you separate your data and tables is dependent on your reporting and application needs.
The following is a high level example of …

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Unindexed queries can be really expensive

The story happened with a webshop application running on Amazon EC2 microinstances. Actually on two instance. Amazon business model is basically simple, they ask money for only three things: Cpu time, IOPS and network traffic. Everybody (including me) thinks for the first time network traffic will be the bottleneck until they got the first bill (it can be even after one year considering the free tier). Actually in this category the IOPS is the most expensive.

Symptoms

On the cacti diagrams I saw strange datas. The created temp tables on disk and created temp files were much higher than created temp tables. The 67% of temporary tables were created on disk. This is very far from optimal.

Temporary objects in MySQL

Quick patch

II increased the max_heap_table_size and tmp_table_size from …

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MySQL Tech Tour New York

Tuesday, February 21, 2012
10:30 AM – 3:00 PM
Oracle Office
520 Madison Ave, Suite 3000
New York, 10022

Register Here!

You’re Invited – Oracle’s MySQL Tech Tour Event – New York, NY

Join us for our latest Tech Tour event in New York. Get information and advice direct from the MySQL technical experts. In these sessions, we will demonstrate how to better develop, integrate, secure, and tune MySQL for your application.

Morning Session:

MySQL Fundamentals

Fundamental Capabilities
Deployment options
Development tools
Suggested next steps

Afternoon Session: Best Practices

Deploying Large & Mission Critical MySQL Applications

Architecture
High Availability & …

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The Full Monty – Version 2

Installing MySQL on CentOS 6.2 with PaceMaker, MHA and more

When I work with High Availability software, I’m reminded of the maze in the original computer adventure game “You are Lost in a maze of twisty-turny passages all alike…”.

If you search the web for HA programs you will find many well maintained projects all related that refer each other. The goal of this document is to give you with a step by step guide to a production worthy MySQL system. It should provide at least 99.999% access to your data and be able to scale read requests as you grow.

I have chosen these programs and utilities because they are free (as in beer) and each has enterprise support available. (When you make the money to pay for it.) If you start with this MySQL platform you will avoid many common problems. Just write your application to read and write data from different servers.

Here is what we’ll be …

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My talks on PL MySQL Conference (+free book inside)

On coming PL MySQL conference 2012 I will give one tutorial:
Percona XtraBackup: install, usage, tricks. This tutorial I will do in joint with Alexey Kopytov, the lead developer of Percona XtraBackup. Our intent is to provide the comprehensive overview of the XtraBackup architecture and features, and we will touch future roadmap. This is all first-hand information from the main architect and lead developer.

And two talks:

. There I will cover XtraDB Cluster features and usage scenarios.

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Open APIs are the new open source

We’ve seen the rise of open source software in the enterprise and also beyond the IT industry, but the real keys to openness and its advantages in today’s technology world — where efficient use of cloud computing and supporting services are paramount — exist in open application programming interfaces, or APIs.

Open source software continues to be a critical part of software development, systems administration, IT operations and more, but much of the action in leveraging modern cloud computing and services-based infrastructures centers on APIs. Open APIs are the new open source.

Read the full story at LinuxInsider.

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