Here’s a little snippet which mysqldumps only the databases with a specific prefix or another wildcard expression under windows command line or windows batch.

@echo off
setlocal enabledelayedexpansion
set myvar=
for /f %%i in ('c:xamppmysqlbinmysql -uroot -pmysql -e "SHOW DATABASES LIKE 'prefix_%%'"') do set myvar=!myvar! %%i
echo %myvar:~10%
@echo on
c:xamppmysqlbinmysqldump.exe -u root --password=mysql --databases %myvar:~10% | "c:Program Files (x86)gzipgzip.exe" > "C:WHEREEVERYOUWANTmysqlbackup-%date:~6,4%-%date:~3,2%-%date:~0,2%-%time:~0,2%-%time:~3,2%-%time:~6,2%.gz"

The challenge: How to distribute additional content-packages for an Adobe Air App for iOS and Desktop.

The Answer: Inspired by this article I started coding my own ActionsScript tar version to unpack gnu-tar files. This format has some benefits. First it is one file, easy downloadable and shareble. Because it’s uncompressed, it is faster than any compressed format like zip. This doesn’t really matter because all files in my packages are compressed files like jpeg. I unpacked a 350 MB file on an iPad 2 in 18 seconds. Additionally it is very fast to extract only one file or data out of it, maybe for some metainformation. Possibly there is some potential to optimize the speed. It’s a common used format, so packing tools are available on all plattforms (Windows, Mac OSX and Linux). Because of this there is no need to code a special packing tool.

And last, I want to share this with you:

AS3 Simple Untar on Google Code

Have fun with it.