Laravel中的透视表

Schema::create('users', function (Blueprint $table) {
    $table->id();
    $table->string('name');
    $table->timestamps();
});

Schema::create('roles', function (Blueprint $table) {
    $table->id();
    $table->string('name');
    $table->timestamps();
});

Schema::create('role_user', function (Blueprint $table) {
    $table->id();
    $table->unsignedBigInteger('user_id');
    $table->unsignedBigInteger('role_id');
    $table->timestamps();

    $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
    $table->foreign('role_id')->references('id')->on('roles')->onDelete('cascade');
});

class User extends Model
{
    public function roles()
    {
        return $this->belongsToMany(Role::class);
    }
}

class Role extends Model
{
    public function users()
    {
        return $this->belongsToMany(User::class);
    }
}

$user = User::find(1);
$roles = $user->roles; // 获取用户的所有角色

$role = Role::find(1);
$users = $role->users; // 获取拥有该角色的所有用户

$user = User::find(1);
$roles = $user->roles()->withPivot('additional_field')->get();

$user = User::find(1);
$role = Role::find(1);

// 关联角色
$user->roles()->attach($role->id);

// 解除关联
$user->roles()->detach($role->id);

// 同步关联（更新）
$user->roles()->sync([$role->id]);

$user = User::find(1);
$roles = $user->roles()->withPivot('additional_field')->get();