Laravel Eloquent 从多个表中查询 Select 列

Question

I have a Laravel backend and a VueJS frontend.

I'm trying to produce a query on a model with a hasOne relationship but only select specific columns from the relationship, do a sum and a group by.

Models

• Contract (CONTRACT_TYPE, CONTRACT_PRICE)
• AdditionalInfo (START_DATE)

My Eloquent Query

public function contractsByYear() {
   return Contract::where('CONTRACT_TYPE','LIKE','SP-%')->with(['AdditionalInfo' => function($query) {
       $query->selectRaw('MONTH(START_DATE) as Month')->whereYear('START_DATE','2019');
   }])->sum('CONTRACT_PRICE')->groupBy('Month');
}

Expected Results

MONTH | TOTAL
1     | 500
2     | 233
3     | 800
etc

My issue is the table structure is existing and I can't edit. Why the START_DATe is stored in a separate table is beyond me.

Answer 1

Collection methods will probably do what you want

public function contractsByYear()
{
    return Contract::select('id', 'CONTRACT_PRICE') /* Only really need the id (or whatever else is the pk) and the price */
    ->where('CONTRACT_TYPE','LIKE','SP-%')
    ->with(['AdditionalInfo' => function($query) {
        $query->select('id', 'contract_id')         /* Only really need the id (or whatever else is the pk), and the Contract fk*/
        ->selectRaw('MONTH(START_DATE) as Month')   /* Aggregate the month */
        ->whereYear('START_DATE','2019');
    }])
    ->get()
    // From this point on, it's a Collection
    ->groupBy('AdditionalInfo.*.Month')             /* It's either this or 'AdditionalInfo.Month' */
    ->map(function($item, $key) {
        return [
            'month' => $key,
            'total' => $item->sum('CONTRACT_PRICE')
        ];
    });
}