MySQL keeps many different files, some contain real data, some contain meta data. Witch ones are important? Witch can your throw away?

This is my attempt to create a quick reference of all the files used by MySQL, whats in them, what can you do if they are missing, what can you do with them.

When I was working for Dell doing Linux support my first words to a customer where “DO YOU HAVE COMPLETE AND VERIFIED BACKUP?” Make one now before you think about doing anything I suggest here.

You should always try to manage your data through a MySQL client.  If things have gone very bad this may not be possible. MySQL may not start. If your file system get corrupt you may have missing files. Sometimes people create other files in the MySQL directory (BAD).  This should help you understand what is safe to remove.

Before you try to work with one of these files make sure you have the file permissions set …

HandlerSocket is cool. But, it turns out there are a few issues.

Justin Swanhart points out HandlerSocket currently lacks atomic operations . Since HandlerSocket uses different connections for reading and writing, you can’t increment/decrement a value without creating a race condition.

Still, the idea of skipping SQL interpretation and just reading the data you know you want is a great one.  Writing data might even be better. But being able to use both SQL and NoSQL could be really wonderful.  What if we could use complex queries to update complex tables and pluck values out as needed.  For example, queries to analyze current weather conditions and produce forecasts that we could then retrieve via a location key? What about updating current condition data …

We're publishing a new Strata Gem each day all the way through to December 24. Yesterday's Gem: Turn MySQL into blazing fast NoSQL.

Tomorrow's augmented reality is being built today on mobile devices. The Tasker application for Android is a fun platform for prototyping personal automation and sensing applications. Described modestly as an application which "performs tasks based on contexts," it gives non-programmers access to the sensing and system features of the phone.

Following a simple rule metaphor of taking action upon matched conditions, Tasker can respond …

One of the themes from News Foo that continues to resonate with me is the importance of data journalism. That skillset has received renewed attention this winter after Tim Berners-Lee called analyzing data the future of journalism.

When you look at data journalism and the big picture, as USA Today's Anthony DeBarros did at his blog in November, it's clear the recent suite of technologies is part of a continuum of technologically enhanced storytelling that traces back to computer-assisted reporting (CAR).

As DeBarros pointed out, the message of CAR …

We're publishing a new Strata Gem each day all the way through to December 24. Yesterday's Gem: What your inbox knows.

The trend for NoSQL stores such as memcache for fast key-value storage should give us pause for thought: what have regular database vendors been doing all this time? An important new project, HandlerSocket, seeks to leverage MySQL's raw speed for key-value storage.

NoSQL databases offer fast key-value storage for use in backing web applications, but years of work on regular relational databases has hardly ignored performance. The main performance hit with regular databases is in interpreting queries.

Series

What are the chances for a free software cloud?

• Resolving the contradictions between web services, clouds, and open source
• Defining clouds, web services, and other remote computing
• Why clouds and web services will continue to take over computing
• Why web services should be released as free …

We're publishing a new Strata Gem each day all the way through to December 24. Yesterday's Gem: Kinect democratizes augmented reality.

Today's databases are designed for the spinning platter of the hard disk. They take into account that the slowest part of reading data is seeking: physically getting the read head to the part of the disk it needs to be in. But the emergence of cost effective solid state drives (SSD) is changing all those assumptions.

Over the course of 2010, systems designers have been realizing the benefits of using SSDs in data centers, with major IT vendors and companies adopting them. Drivers for SSD adoption …

Series

What are the chances for a free software cloud?

• Resolving the contradictions between web services, clouds, and open source
• Defining clouds, web services, and other remote computing
• Why clouds and web services will continue to take over computing
• Why web services should be released as free software (12/20)
• Reaching the pinnacle: truly open web services and clouds (12/22)
…

One of the Department of Energy's flagship open government initiatives, Open Energy Information (OpenEI), was on display at the recent National Science Festival. Ryan McKeel, an engineer at the National Renewable Energy Laboratory, talks about how OpenEI provides access to data, models and tools in the following clip:

OpenEI is "open" in any number of important ways, including open source and open linked data, as Debbie Brodt-Giles, the OpenEI project leader, notes in an Amazon case study (OpenEI is hosted on Amazon's Web Services platform). "Key platform software for OpenEI includes Apache, Semantic MediaWiki, MySQL, and …

1. Using MysQL as NoSQL -- 750,000+ qps on a commodity MySQL/InnoDB 5.1 server from remote web clients.
2. Making an SLR Camera from Scratch -- amazing piece of hardware devotion. (via hackaday.com)
3. Mac App Store Guidelines -- Apple announce an app store for the Macintosh, similar to its app store for iPhones and iPads. "Mac App" no longer means generic "program", it has a new and specific meaning, a program that must be installed through the App store and which has limited functionality …