WhereIN data for calculations for displaying results - laravel

Question

I am trying to work out the best practice to calculate Avg Attendance.
I would like to show this on the Member View (html part is no issue)
I have the following 3 databases
Members DB
|id|first|last|..........
|1 |.....................
|2 |.....................
Rolls DB
|id|roll_id|member_id|status|
|1 |1 |1 |P |
|2 |1 |2 |V |
|3 |2 |1 |A |
|4 |2 |2 |C |
Rollmappings DB
|id|roll_date |roll_year|
|1 |2019-03-01|2019 |
|2 |2019-03-02|2019 |
I have the following in my Member Model
public function roll()
{
return $this->hasMany('App\Roll');
}
I have the following in my Roll Model
public function rollmapping()
{
return $this->hasOne('App\Rollmapping', 'id','roll_id');
}
I would like to count all records which does not equal "A"
So in the code blocks above Member 1 will needs to show me 50% attendance, and member 2 will show me 100% attendance.
I would need to have something in place which will auto roll over when we move into 2020
I do Have Carbon Date installed with the app as well
I got stuck on the link on pulling the year_roll into the select for the Roll and to count I can use:
$rollyear = Rollmapping::lastest()->value('roll_year');
$totalweeks = DB::table('rollmappings')
->where('roll_year', '=', $rollyear)
->get()
->count();
But I am stuck on on pulling the correct records from the roll using the roll_id as I only want the roll_id which have a year date of the current year.
Thanks

Answer 1

If I understand you're question correctly then you should be able to get what you need using whereHas
$count = Roll::whereHas('rollmapping', function ($query) {
$query->whereYear('roll_date', now()->year);
})->count();
If you would also like to exclude all the rolls where the status does not equal A then you would have something like:
$count = Roll::whereHas('rollmapping', function ($query) {
$query->whereYear('roll_date', now()->year);
})
->where('status', '!=', 'A')
->count();