  Databases are an indispensable resource for retrieving up-to-date
information. However, curious database operators may be able to find out the
users' interests when the users buy something from the database. For these
cases, if the digital goods have the identical prices, then a $k$-out-of-$n$
oblivious transfer protocol could help the users to hide their choices, but
when the goods have different prices, this would not work. In this paper, we
propose a scheme to help users to keep their choices secret when buying priced
digital goods from databases.
