Compare Eloquent Models with is() and isNot()

Compare two Eloquent model instances using is() and isNot() to verify matching primary keys, table names, and database connections.

Comparing model identity using equality operators ($user1 == $user2) compares all model attributes, which fails if one model has dirty attributes or loaded relationships. Comparing raw IDs ($user1->id === $user2->id) fails if one of the variables is null or a different model type.

The is() and isNot() methods verify whether two instances represent the exact same database record.

Comparing Models

use App\Models\User;

$currentUser = auth()->user();
$postAuthor = $post->author;

// Manual ID comparison (risks null pointer if postAuthor is null)
if ($postAuthor && $currentUser->id === $postAuthor->id) {
    // ...
}

// Clean Eloquent model comparison (safe against null)
if ($currentUser->is($postAuthor)) {
    // Both represent the same user on the same database connection
}

Negated Comparison with isNot()

if ($currentUser->isNot($postAuthor)) {
    abort(403, 'You are not the author of this post.');
}

What is() Verifies

1. The comparison object is not null.
2. Both models share the same primary key value.
3. Both models share the same database table name.
4. Both models share the same database connection name.

Summary

• Safe from null reference exceptions when comparing optional relationships.
• Compares database identity instead of serialized in-memory attributes.
• Improves authorization checks and policy logic readability.