Adding closure to select raw queries (sum) - laravel

Question

I have many different combinations of select sum from the same table but with slightly different where queries.
foreach ($transactionTypes as $type) {
switch($type) {
case 'Fuel':
$values = \DB::table("transactions")
->select(\DB::raw("user_id, SUM(fuel_charge) as fuel_charges"))
->whereIn('type', ["Charge", "Refund"])
->whereIn('user_id', $userIdsToBeUsed)
->whereDate('created_at', '>=', $fromDate->toDateString())
->whereDate('created_at', '<=', $toDate->toDateString())
->groupBy('user_id')
->get();
break;
case 'Commission':
$userIdsToBeUsed = $userIds->merge($tier3Ids);
$values = \DB::table("transactions")
->select(\DB::raw("user_id, SUM(commission_charge) as commission_charges"))
->whereIn('user_id', $userIdsToBeUsed)
->whereDate('created_at', '>=', $fromDate->toDateString())
->whereDate('created_at', '<=', $toDate->toDateString())
->groupBy('user_id')
->get();
break;
}
}
As you can see, they are slightly different and I have a dozen of cases in the loop; but with this approach, I need to do a dozen queries to the same table.
What I want to ask is, Is there a way to combine them into a single query?
Something like:
$values = \DB::table("transactions")
->select(
[
\DB::raw("user_id, SUM(fuel_charge) as fuel_charges") => function($q) {
// $q->where(...)
}
],
[
\DB::raw("user_id, SUM(commission_charge) as commission_charges") => function($q) {
// $q->where(...);
}
])
->get()

Answer 1

A quick thought. This can be a pretty neat hack you can say:
$userIdsToBeUsed = $userIds->merge($tier3Ids);
foreach ($transactionTypes as $type) {
$values = \DB::table("transactions")
->select(\DB::raw("user_id, SUM(" . strtolower($type) . "_charge) as " . strtolower($type) . "_charges"))
->whereIn('type', ["Charge", "Refund"])
->whereIn('user_id', $userIdsToBeUsed)
->whereDate('created_at', '>=', $fromDate->toDateString())
->whereDate('created_at', '<=', $toDate->toDateString())
->groupBy('user_id')
->get();
}
I just use the lowercase of $type in query