my $citydata = $dbh->exec_select( "select city,state from mytable whe
+re city = ?", $city );
my @states = map {$_->{state}} @$citydata;
my $statedata = join ' OR ', map { "state = ?" } @$citydata;
my $codedata = $dbh->exec_select( "select code from othertable where
+(year=2014 and ($statedata)), @states );