public function getProductsCategories()
{
return $this->hasMany(Categories::className(), ['id' => 'category_id'])->viaTable(CategoryProduct::tableName(), ['product_id' => 'id']);
}
public function getSelectedArray($product_id)
{
$query = (new Query())->from(CategoryProduct::tableName())->where(['product_id' => $product_id]);
$items = [];
foreach ($query->all($this->db) as $row) {
$items[] = (int) $row['category_id'];
}
return $items;
}