Help with some contoller

Hello, I would like controller that can connect wirelessly to some ip address and read and change some existing data on a data base?

Witch Arduino parts I need to use?

thank you!

You could use an Arduino with a wifi shield. I use for example an ethernet shield with a wifi client device. But for wifi you can also use other kinds of hardware (arduino compatible like XBee or non-Arduino things like IMP).

Does it have to be an Arduino ?

If the code is limited (only ethernet and SD card interfacing), and Arduino Uno is good or an Arduino Ethernet, but if you need a lot more code you can use the Arduino Mega 2560. For wifi are a number of possibilities.