my ($sid, $age) = $dbh->selectrow_array(<<'SQL', undef, $uid);
SELECT SessionID,
       datediff(minute, TimeStamp, getdate())
  FROM Sessions
 WHERE UserID = ?
    AT ISOLATION READ UNCOMMITTED
SQL


my %data =
   ( Column1 => $value1,
     Column2 => $value2,
     # ...
     ColumnN => $valueN,
   );

my $rv = $dbh->do(<<"SQL", undef, values %data);
INSERT
  INTO TableName (@{[ join ', '  keys %data ]})
VALUES ( @{[join ', ', map {'?'} keys %data ]})
SQL