How to interpret the date fields in database?

How do you interpret the integer value in the order_created field that is in the jos_hikashop_order table?

We are using this value in an ODBC connection and can't figure out how to interpret this field as a valid date.

That's a unix timestamp: en.wikipedia.org/wiki/Unix_time

You can easily convert it to a date using the date() function of PHP: php.net/manual/en/function.date.php
or the hikashop_getDate() function which handles automatically the timezones based on your joomla settings.