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Running MySQL queries on multiple servers

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HowTos

You may know how to use SQL to extract data from a table in a MySQL database, and how to run a query that combines data from more than one table. But what about multiple databases? Or even multiple databases on multiple servers?

Let's start by looking at the simplest example -- running a query on a single table. All you have to do is connect to the database, enter the query, and press Enter.

By the way, I'm using David Nash's HYG Databases of stellar data in the following examples. I downloaded Nash's CSV files, wrote a shell script to format them, then created the databases on three of my servers -- Acamas, Cassandra, and Hector.

Full Story.

I prefer Linux in almost every way to Mac OS X, but I have to admit a little envy over OS X's Exposé feature, which quickly tiles all open windows. Luckily for Linux users, Komposé brings the same convenience to the Linux desktop.

Komposé is a task manager for KDE that generates thumbnails of your windows grouped by your current workspace or all workspaces. The old-school way to manage windows is to use a taskbar or to move through your windows by using Alt-Tab and Alt-Shift-Tab. I usually have 10 to 20 windows open on each virtual desktop, however, so this can get tedious pretty fast.

That Story.

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