Get a random value from a dataset that meets "WHERE clause" criteria

Hello all,
I have a situation where I need to get a random value from a dataset, but it has to be a value within the dataset where the dataset’s “created_date” column value is less than a specified date.

So, for example, if I have a specified date of 11/25/2010, then I need to get a random row in the dataset that has “created_date” column value less than 11/25/2010.

I think that the from_dataset function will only return a single value rather than a set (although I’d be quite happy to be wrong on that). So I’m thinking I will need to use a schema column from which I can select a random value. I’m just not sure how to specify the “where date < given_date”.

All help is appreciated.