如何获取订单计数- SQL

Question

每次我尝试运行下面的SQL时，我都会得到和SQL错误( 'field list‘中的未知列's01_Orders.id’)：

SELECT
  SUM(agg.Total) as orderTotal,
  SUM(agg.NoShip) as orderTotalNoShip,
  COUNT(s01_Orders.id) as ordercount
FROM
  (
    SELECT
      o.total AS "Total",
      o.total - oc.amount AS "NoShip"
    FROM
      s01_Orders o
      JOIN s01_OrderDiscountTotals odt ON o.id = odt.order_id
      LEFT JOIN s01_OrderCharges oc ON o.id = oc.order_id
      AND oc.type = "SHIPPING"
      AND o.ship_cntry = "US"
    WHERE
      odt.coupon_id = "1395"
    GROUP BY
      odt.order_id
  ) agg

当我省略以下内容时，它可以正常工作：

COUNT(s01_Orders.id) as ordercount

s01_orders表和列已经存在-任何帮助都将不胜感激。

Answer 1

子查询没有选择s01_Orders.id

  SELECT
  SUM(agg.Total) as orderTotal,
  SUM(agg.NoShip) as orderTotalNoShip,
  ordercount
  FROM
 (
SELECT
  o.total AS "Total",
  o.total - oc.amount AS "NoShip",
  COUNT(o.id) as ordercount
FROM
  s01_Orders o
  JOIN s01_OrderDiscountTotals odt ON o.id = odt.order_id
  LEFT JOIN s01_OrderCharges oc ON o.id = oc.order_id
  AND oc.type = "SHIPPING"
  AND o.ship_cntry = "US"
WHERE
  odt.coupon_id = "1395"
GROUP BY
  odt.order_id
) agg

尝试上面的查询，它选择了count，并将相应地工作。