如何在 Laravel Eloquent 中构建具有多级关系的查询

Question

I have three models. Sponsor , Optin and Participant . Sponsor has a one-to-many relationship with Optin and Optin has a one-to-one Participant .

Which make the models look like this:

Sponsor model

class Sponsor extends Model
{ 
    public function optins()
    {
        return $this->hasMany(Optin::class);
    }
}

Optin model

class Optin extends Model
{    

    public function sponsor()
    {
        return $this->belongsTo(Sponsor::class);
    }
    public function participant()
    {
        return $this->belongsTo(Participant::class);
    }
}

Participant model

class Participant extends Model
{
    public function optins()
    {
        return $this->hasMany(Optin::class);
    }

    public function scopeCreatedToday($query)
    {
        return $query->whereDate('created_at', Carbon::today());
    } 
}

Now in a daily scheduled task I want to iterate through all participants that where created today and that opted in to a certain Sponsor to send them like an email or something. Now I got as far as echoing the id's of the belonging participants. But the next step is to get the participant object and filter them by the right created date. But I am a little lost on how to handle this.

$sponsor = Sponsor::find(1);
$count = $sponsor->optins()->count();
echo("Count: " . $count . "\n");
$optins = $sponsor->optins()->get();
foreach($optins as $optin)
{
    echo($optin->participant_id . "\n");
}

EDIT: After rethinking the structure I figured out that Optin has a many-to-one relation with Participant .

Answer 1

Step 1 is to define the relationship between Sponsor and Participant models using a belongsToMany relationship. I assume your optins table has both participant_id and sponsor_id columns.

class Sponsor extends Model
{ 
    public function optins()
    {
        return $this->hasMany(Optin::class);
    }
    public function participants()
    {
        return $this->belongsToMany(Participant::class, 'optins');
    }
}

Then you want to eager load the relationship using the with() method, and also filter it based on your condition of the creation date. This will make the participants available as a collection.

$date = now()->subDay(); // or whatever you like.
$start = $date->startOfDay();
$end = $date->endOfDay();

$sponsor = Sponsor::where('id', 1)
    ->with([
        'participants' => function($q) use ($start, $end) {
            $q->whereBetween('created_at', [$start, $end]);
        }
    ]);

$count = $sponsor->participants->count();
echo("Count: $count\n");
foreach($sponsor->participants as $participant)
{
    echo("$participant->name\n");
}

Answer 2

Since Participant has a one-to-many relation with Optin I added the following relation on the Sponsor model. With the passing the Optin model als a second parameter to the belongsToMany method, since it functions as an intermediate table.

public function participants()
{
    return $this->belongsToMany(Participant::class, Optin::class);
}

From there out I could easily get all the participants with adding subqueries belonging to the sponsor like so:

$sponsor = Sponsor::find(1); 
$participants = $sponsor->participants()->createdToday()->get();
foreach($participants as $participant)
{
    //do something with $participant
}

Answer 3

if you want multi level data from same table this solution help you with hasmany relationship in laravel.and with('point') is function name.your name will be diferent.

class Master extends Model
{
    public function point() {
        return $this->hasMany(Master::class,'point_id')->with('point');
    }
}

Answer 4

please try to define the primary key's of all models and when use the function's set the foreign keys of every function