mysql - 带有 INNER JOIN 和 WHERE 的 SQL 查询

Question

尝试在查询中获取特定值时收到以下消息

“指定的字段可以引用多个表”

很明显，我正在尝试搜索多个表中存在的内容，但是如何正确执行此操作？

现在我有以下代码：

SELECT Table1.CustomerId, Table1.Address, 
       Table2.CustomerId, Table2.Telephone, 
       Table3.CustomerId, Table3.Notes
FROM (Table1 INNER JOIN Table2 ON Table1.CustomerId=TAble2.CustomerId) 
      INNER JOIN Table3 ON Table2.CustomerId=Table3.CustomerId
WHERE CustomerId = 0015

最后一句话是问题......有什么想法吗？

Answer 1

错误消息非常清楚，子句CustomerId中的字段同时出现在两个表中。您必须确定要从哪个表中使用它；还是？例如：WHEREWHERE CustomerId = 0015table1table2

SELECT Table1.CustomerId, Table1.Address, 
       Table2.CustomerId, Table2.Telephone, 
       Table3.CustomerId, Table3.Notes
FROM (Table1 INNER JOIN Table2 ON Table1.CustomerId=TAble2.CustomerId) 
      INNER JOIN Table3 ON Table2.CustomerId=Table3.CustomerId
WHERE table1.CustomerId = 0015

Answer 2

CustomerId您应该在 WHERE 语句中指出哪个表来自

SELECT Table1.CustomerId, Table1.Address, 
       Table2.CustomerId, Table2.Telephone, 
       Table3.CustomerId, Table3.Notes
FROM (Table1 INNER JOIN Table2 ON Table1.CustomerId=TAble2.CustomerId) 
      INNER JOIN Table3 ON Table2.CustomerId=Table3.CustomerId
WHERE Table1.CustomerId = 0015

Answer 3

您需要从需要 customerId 的表中初始化。

SELECT Table1.CustomerId, Table1.Address, 
       Table2.CustomerId, Table2.Telephone, 
       Table3.CustomerId, Table3.Notes
FROM (Table1 INNER JOIN Table2 ON Table1.CustomerId=TAble2.CustomerId) 
      INNER JOIN Table3 ON Table2.CustomerId=Table3.CustomerId
WHERE table1.CustomerId = 0015