$Product = $ProductClass->getProduct();

// 同一顧客購入回数制限(設定されていなければ0)
$kaisuLimit = $Product->getKaisuLimit();

if ($this->app->isGranted('ROLE_USER')) {
$Customer = $this->app->user();
if($kaisuLimit != "" && $kaisuLimit <= 実際の商品購入回数){
$limit = $kaisuLimit;
$this->addError('cart.over.kaisu_limit', $productName);
$this->removeProduct($ProductClass->getId());
return $limit;
}
}

select o.customer_id, od.product_id, count(*)
from dtb_order as o inner join dtb_order_detail as od
on o.order_id=od.order_id
group by o.customer_id, od.product_id

public function getOrderedCount(\Eccube\Entity\Product $Product, \Eccube\Entity\Customer $Customer)
{
$result = $this->createQueryBuilder('od')
->select('COUNT(od.Product)')
->innerJoin('od.Order', 'o')
->Where('od.Product = :Product')
->andWhere('o.Customer = :Customer')
->setParameter('Product', $Product)
->setParameter('Customer', $Customer)

->getQuery()
->getResult();

return $result;
}
}