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sortinglaravelmany-to-manyeloquentrelationship

Sorting a many to many relation with Laravel Eloquent

I do have swatches table, a colors table and a swatch_color pivot table.

Relations are set as:

public function colors()
{
    return $this->belongsToMany('Color');
}

public function swatches()
{
    return $this->belongsToMany('Swatch');
}

I have no problem to retrieve the swatches with the color relations

$swatches = Swatch::with('colors')->get();
return dd($swatches);

Colors is always an array of 5 color objects with hue, R, G, and B attributes.

Now I would like to sort the swatches by the R value of the first related color.

Solution

  • This is all you need to sort $swatches collection:

    $swatches->sortBy(function ($swatch) {
  return ($color = $swatch->colors->first())
     ? $color->r
     : null;
});

    Another way would be manual joining the tables.

    You can use sortByDesc for descending order.