Converting database value into date

[gavinzac]

I want to make a graph of home many users i've had each month over the last 12 months. like, July - 0, August - 200, September 320, and so on, a cumulative graph rather than home many joined in each month. i'd also like to be able to compare 2 months side by side, eg using a bar chart or "planet" chart.

to do this i need to convert the long number representing the registration date in the database into a proper date. how do i go about this?

thanks,
gav