SELECT Shippers.ShipperName,COUNT(Orders.OrderID) AS NumberOfOrders FROM Orders
LEFT JOIN Shippers
ON Orders.ShipperID=Shippers.ShipperID
GROUP BY ShipperName;
最佳答案
你可以试试这个:
$this->db->select('Shippers.ShipperName,COUNT(Orders.OrderID) AS NumberOfOrders');
$this->db->join('Shippers', 'Orders.ShipperID = Shippers.ShipperID', 'left');
$this->db->group_by('ShipperName');
$getResult=$this->db->get('ShipperName');
关于mysql - 如何使用 $this->db 编写以下 sql 查询,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/25840823/