The parameters to this method can be either one or multiple strings, or a single array
of relation names and the optional callbacks to customize the relations.
A relation name can refer to a relation defined in [[ActiveQueryTrait::modelClass|modelClass]]
or a sub-relation that stands for a relation of a related record.
For example, orders.address means the address relation defined
in the model class corresponding to the orders relation.
The following are some usage examples:
php
find customers together with their orders and country
Customer::find()->with('orders', 'country')->all();
find customers together with their orders and the orders' shipping address
Customer::find()->with('orders.address')->all();
find customers together with their country and orders of status 1
Customer::find()->with([
'orders' => function (\yii\db\ActiveQuery $query) {
$query->andWhere('status = 1');
},
'country',
])->all();
