Simple Datetime format in form of YYYYMMDD
<p>I have a little problem with time format
I would like to get an output of the form <code>YYYY-MM-DD</code> given the datetime data input as <strong>19901209</strong> which is <code>1990-12-09</code>.</p>

<p>I would also like to know if there is any way to get the data in other formats as well, for example, <code>DD-MM-YYYY</code> or <code>MM-DD-YYYY</code> given the data formated in the form as specified i.e <strong>19901209</strong>.</p>

<p>Thank you so much in advance.</p>
