Expanding a little on RMGir's post - you could conditionally build the SQL statement depending on the options selected and do all of the calculations/aggregates there.

eg

$sql = "select ";
$joiner = " ";
foreach (@enable_opts) {
   $sql .= $joiner . $_ . "(column)";
   $joiner = ",";
}
$sql .= " from table where column = ?"; 
#etc
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rdfield