1. A method for processing predicates in an iterator function, comprising: when an iterator function included in a statement is invoked, obtaining one or more predicates included in the statement; applying the one or more predicates to a row of data; if applying the one or more predicates results in a match, returning the row of data; and if applying the one or more predicates does not result in a match, searching for another row of data for which application of the one or more predicates results in a match.