在 Laravel Eloquent 中，全局作用域自動應(yīng)用于每次查詢，適合如過濾非活躍用戶等場景；局部作用域需手動調(diào)用，適合如僅在特定上下文中顯示已發(fā)布文章的場景。1. 全局作用域通過實現(xiàn) Scope 接口并在模型中注冊，例如添加 where('active', true) 條件。2. 局部作用域是模型中的方法，以 scope 開頭，可帶參數(shù)，如 scopeVerified() 或 scopeOfType()。3. 使用全局作用域時應(yīng)考慮其對所有查詢的影響，必要時可用 withoutGlobalScopes() 排除。4. 選擇作用域時，根據(jù)是否始終需要應(yīng)用條件決定，同時注意代碼的可讀性和可測試性。5. 簡單的全局作用域可通過閉包定義，提升開發(fā)效率。

In Laravel Eloquent, understanding how to define and use local and global scopes is key to writing clean, reusable, and maintainable code. Scopes help you filter query results without repeating the same conditions across your application. Here’s how to make the most of them.

What's the difference between local and global scopes?

Global scopes apply automatically every time you query a model — like always filtering out deleted users or only fetching active records.
Local scopes, on the other hand, are applied manually when needed — for example, only showing published posts in certain contexts.

Knowing when to use each helps keep your logic organized and prevents bugs from unintended data exposure.

How to define a global scope

To create a global scope, you need to implement the Illuminate\Database\Eloquent\Scope interface. This involves defining a class with an apply method that adds constraints to the query.

For example, let’s say you want to exclude inactive users globally:

namespace App\Scopes;

use Illuminate\Database\Eloquent\Builder;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Scope;

class ActiveUserScope implements Scope
{
    public function apply(Builder $builder, Model $model)
    {
        $builder->where('active', true);
    }
}

Then, in your model:

use App\Scopes\ActiveUserScope;

protected static function booted()
{
    static::addGlobalScope(new ActiveUserScope);
}

Now, every query on this model will include where active = true.

Note: You can bypass global scopes using methods like withoutGlobalScopes() or withoutGlobalScope(ActiveUserScope::class) if you ever need to fetch all records.

Creating and using local scopes

A local scope is simpler — it's just a method inside your model that starts with scope, followed by the name in camelCase.

For example, to define a scope that returns only verified users:

public function scopeVerified(Builder $query): Builder
{
    return $query->whereNotNull('email_verified_at');
}

Then call it like this:

User::verified()->get();

You can also add parameters:

public function scopeOfType(Builder $query, string $type): Builder
{
    return $query->where('type', $type);
}

And use it like:

User::ofType('admin')->get();

These scopes are great for reusing common filters without cluttering your controllers.

When to choose global vs local scopes

• Use global scopes when the condition should always be applied (like soft-deletes, tenant isolation, status checks).
• Use local scopes when the filter is context-dependent (e.g., filtering by category, status, or custom user roles).

Also, consider readability and testability:

• Global scopes are powerful but can be harder to track down when debugging.
• Local scopes are more explicit and easier to understand at a glance.

Some tips:

• Document any global scopes so future developers know they exist.
• Don’t overdo it with too many scopes — sometimes a simple where clause is clearer.
• Group related scopes into traits or base models if you find yourself copying them.

Bonus tip: Using anonymous global scopes

If your scope is simple, you can skip creating a separate class and use a closure directly in the model:

use Illuminate\Database\Eloquent\Builder;
use Illuminate\Support\Facades\Auth;

protected static function booted()
{
    static::addGlobalScope('user_tenant', function (Builder $builder) {
        $builder->where('user_id', Auth::id());
    });
}

This is handy for quick filters that don’t need reuse across multiple models.

Basically, scopes are one of those tools in Laravel that, once understood, make your code cleaner and more expressive. Whether you're applying a global rule or adding a conditional filter, knowing which scope to use and how keeps things running smoothly.

No magic — just smart, reusable query logic.

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