my %ItemUID = ();
my %ItemName = ();

#Get ItemUID and Item Name (ItemUID is unique to each Test.IData)
{
    my $sql = "SELECT t.IData FROM Tests AS t JOIN Assignments AS a ON a.A
+ssignmentTestID=t.ID JOIN Users AS u ON u.ID=t.UserID WHERE u.Institu
+tionID='004452' AND t.IData REGEXP 'ch01.03.MultipleChoice 049';";

    my $sth = $dbh->prepare($sql);
    $sth->execute();

    while ( my @row = $sth->fetchrow_array() ) {
        my $idata = $row[0];
        while ( $idata =~ /<item([^>]+)/gi ) {
            my $elements = $1;
            my $src;
            my $uid;
            if ( $elements =~ /src=\"\w+\/([^"]+)/i ) { $src = $1 }
            if ( $elements =~ /uid=\"([^"]+)/i ) { $uid = $1 }
            if ( not exists $ItemUID{$uid} ) {
                $ItemUID{$uid} = $src;
                push(@{$ItemName{$src}}, $uid);
            }
        }
    }
    $sth->finish();
}

# you can generate an array of the unique names if you like
my @names = sort keys %ItemNames;