Amazon SimpleDB now has support for a SQL-like language for
queries. Modified to support multi-valued attributes....the
following query returns all the items which have the values
'Book' and 'Hardcover' in keyword:
select * from my domain where every(keyword) in ('Book',
'Paperback')
http://aws.typepad.com/aws/2008/12/simpledb---now-with-select.html