MySQL：联接表的别名-故障排除

我这里有一个关于SQL fiddle的工作示例：

使用以下查询：

SELECT *
FROM (Orders JOIN 
     Salesperson ON 
     Salesperson.ID = Orders.salesperson_id) 
      JOIN 
     (SELECT salesperson_id AS sid, MAX( Amount ) AS MaxOrder
      FROM Orders
      GROUP BY salesperson_id) AS TopOrderAmountsPerSalesperson
     ON (TopOrderAmountsPerSalesperson.sid=Orders.salesperson_id AND
         TopOrderAmountsPerSalesperson.MaxOrder=Orders.Amount) 

但当我尝试为第一个联接表分配别名时，如下所示：

SELECT *
FROM (Orders JOIN 
     Salesperson ON 
     Salesperson.ID = Orders.salesperson_id) AS SalesOrders
      JOIN 
     (SELECT salesperson_id AS sid, MAX( Amount ) AS MaxOrder
      FROM Orders
      GROUP BY salesperson_id) AS TopOrderAmountsPerSalesperson
     ON (TopOrderAmountsPerSalesperson.sid=SalesOrders.salesperson_id AND
         TopOrderAmountsPerSalesperson.MaxOrder=SalesOrders.Amount) 

我得到一个语法错误。你知道为什么吗

我将其用作别名联接表的资源：

---

您可以为整个查询或表名或字段名提供别名，但不能在联接条件下提供别名。使用

Orders

表的别名

salesforders

尝试以下示例

SELECT *
FROM Orders AS SalesOrders JOIN 
     Salesperson ON 
     Salesperson.ID = SalesOrders.salesperson_id 
      JOIN 
     (SELECT salesperson_id AS sid, MAX( Amount ) AS MaxOrder
      FROM Orders
      GROUP BY salesperson_id) AS TopOrderAmountsPerSalesperson
     ON (TopOrderAmountsPerSalesperson.sid=SalesOrders.salesperson_id AND
         TopOrderAmountsPerSalesperson.MaxOrder=SalesOrders.Amount) 

---

我听不懂你说的话。请再解释一下你是个救生员！我还是很困惑。我的原始join，

订单是否在Salesperson.ID=订单上加入Salesperson.Salesperson\u ID

，是否返回一个表？如果它返回一个表，为什么我不能给这个表分配一个别名？从我最初的问题中，我不明白为什么

（订单加入Salesperson ON Salesperson.ID=订单。Salesperson_ID）作为SalesOrders

不起作用。

（订单加入Salesperson ON Salesperson.ID=订单。Salesperson_ID）作为SalesOrders

这是连接条件，不返回表