Получение данных

Вариант 1 - через ActiveQuery

// SELECT * FROM `customer` WHERE `id` = 123
$customer = Customer::find()
    ->where(['id' => 123])
    ->one();

// SELECT * FROM `customer` WHERE `status` = 1 ORDER BY `id`
$customers = Customer::find()
    ->where(['status' => Customer::STATUS_ACTIVE])
    ->orderBy('id')
    ->all();

// SELECT COUNT(*) FROM `customer` WHERE `status` = 1
$count = Customer::find()
    ->where(['status' => Customer::STATUS_ACTIVE])
    ->count();

// SELECT * FROM `customer`
$customers = Customer::find()
    ->indexBy('id')
    ->all();

Вариант 2 - прямой AR-запрос findOne(), findAll()

// SELECT * FROM `customer` WHERE `id` = 123
$customer = Customer::findOne(123);

// SELECT * FROM `customer` WHERE `id` IN (100, 101, 123, 124)
$customers = Customer::findAll([100, 101, 123, 124]);

$customer = Customer::findOne([
    'id' => 123,
    'status' => Customer::STATUS_ACTIVE,
]);

// SELECT * FROM `customer` WHERE `status` = 0
$customers = Customer::findAll([
    'status' => Customer::STATUS_INACTIVE,
]);

Вариант 3 - через SQL

$sql = 'SELECT * FROM customer WHERE status=:status';
$customers = Customer::findBySql($sql, [':status' => Customer::STATUS_INACTIVE])->all();

Вариант 4 - получение данных в виде массива asArray()

$customers = Customer::find()
    ->asArray()
    ->all();