I am retrieving data from a mysql database and would like to return it as a JSON dict.

```
<?php
if($db->connect_errno > 0){
   die('Unable to connect to database [' . $db->connect_error . ']');
}

$sql = <<<SQL
SELECT tbldomainpricing.extension, tblpricing.msetupfee
FROM `tblpricing`
INNER JOIN tbldomainpricing ON tbldomainpricing.id = tblpricing.relid 
WHERE tblpricing.type = 'domainregister'
SQL;

if(!$result = $db->query($sql)){
    die('There was an error running the query [' . $db->error . ']');
}

$all_rows = array();

while($row = $result->fetch_assoc()) {
 $all_rows []= $row['extension'] . ":" . $row['msetupfee'];
}
header("Content-Type: application/json");
echo json_encode($all_rows);
?>

```

The return :

{"extension":".com","msetupfee":"6.99"},{"extension":".net","msetupfee":"6.99"},

How do I get the return to be

{"com":"6.99"},{"net":"6.99"}

Thanks