Luis Cazares (8/29/2012)
It should be char or varchar.Ideally you should only store the digits and format the phone in the front end. However, you'll need an extra field for extension if needed.
I can imagine international numbers introducing difficulties to this solution (different display formats, therefore need to parse the country code first in a separate column etc etc).
I'd stick with varchar & use suitable constraints and front-end validation to stop rubbish getting in there.
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