Laravel Has Many Merged Laravel Package

Getting Started

Start by installing the package via Composer:

composer require korridor/laravel-has-many-merged

Then, define merged relationships in your Eloquent models using the HasManyMerged trait and the mergedHasMany() method. For example, if a User has many posts and comments, you can merge them into a single activity relationship:

use Korridor\LaravelHasManyMerged\HasManyMerged;

class User extends Model
{
    use HasManyMerged;

    public function posts()
    {
        return $this->hasMany(Post::class);
    }

    public function comments()
    {
        return $this->hasMany(Comment::class);
    }

    public function activity()
    {
        return $this->mergedHasMany([
            'posts' => $this->posts(),
            'comments' => $this->comments(),
        ], 'created_at', 'desc');
    }
}

Your first use case will likely be loading a combined feed: User::with('activity')->get()->first()->activity.

Implementation Patterns

• Unified feed APIs: Encapsulate all user activity in one relationship for use in APIs, notifications, or UI components (e.g., a timeline of Post and Comment instances).
• Centralized sorting/filtering: Apply consistent orderBy, where, and limit rules in one place instead of manually merging collections post-query:

  $user->activity()->where('status', 'published')->limit(20)->get();
  

• Polymorphic-like aggregation without schema changes: Simulate polymorphic relations by merging unrelated tables (e.g., notes, logs, tasks) into activity, even when they don’t share a common table.
• Eager loading and constraints: Use with('activity') and eager-load constraints just like native relationships; the package handles merging logic at query time.
• Extending behavior: Add scoped accessors or scopes that build on the merged relationship:

  public function scopeRecentActivity($query)
  {
      return $query->with(['activity' => fn($q) => $q->limit(10)]);
  }
  

Gotchas and Tips

• Column alignment: All merged relations must share the same column names for ordering/filtering (e.g., all must have created_at, status, etc.). If they don’t, use selectRaw() or accessor mapping in the mergedHasMany() definition to homogenize fields.
• Query builder vs collection merging: This merges queries, not collections—avoid performance pitfalls with large datasets by always using query constraints (e.g., limit, where) before get().
• Ordering consistency: The third argument ('created_at', 'desc') in mergedHasMany() applies globally; if relations have different column names (e.g., updated_at), alias columns in the relationship’s base queries:

  $this->posts()->selectRaw('*, created_at as unified_timestamp')
  

• Pagination Caveats: Direct paginate() on merged relations may produce incorrect offsets due to subquery merging. Prefer simplePaginate() or implement cursor-based pagination if exact counts aren’t required.
• Scout / Search Integration: If using ElasticSearch/Scout, this pattern doesn’t natively index merged data—consider building custom search drivers or syncing a denormalized activity model.