@array1 = [ 1 ,2 , 3];
@array2 = [4, 5, 6];

##</code><code>##

foreach $user(@array1){
$sth -> $dbh ->perpare("INSERT INTO `trial` (User) VALUES ('$user')");
$sth->execute();
 
foreach $time(@array2){
$sth -> $dbh ->perpare("INSERT INTO `trial` (Time) VALUES ('$time')");
$sth->execute();

##</code><code>##

User    Time
1          NULL
2          NULL
3          NULL
NULL    4
NULL    5
NULL    6

##</code><code>##

User      Time
1           4
2           5
3           6