SQL 中未绑定的多部分标识符列

Question

请你帮忙。我正在尝试执行以下操作：

Select tb4.columnName As test1,
   tb2.columnName As test2,
   tb4.columnName As test3 
from [dbname].Table2 tb2, Table1  tb1 
JOIN Table3 tb3 ON tb3.ColumnName = tb1.columnName 
JOIN Table4 tb4 ON tb4.ColumnName = tb3.columnName
JOIN [dbname].Table5 tb5 ON tb5.ColumnName = **tb2.ColumnName**

我得到：

multipart identifier not bound error at ‘tb2.ColumnName’

Answer 1

切勿混用隐式连接（在 from 子句中使用逗号）和显式连接（使用 join ... on 语法）。它们具有不同的优先级，因此在评估最后一个连接条件时，数据库还不知道 tb2。

事实上，始终使用显式连接：几十年来它们一直是标准。您现有的查询似乎缺少 tb2 和 tb1 之间的连接条件，但您想要的逻辑应该是：

select 
    tb4.columnName As test1,
    tb2.columnName As test2,
    tb4.columnName As test3 
from Table2 tb2
inner join Table1 tb1 on ??  -- join condition here
inner join Table3 tb3 on tb3.ColumnName = tb1.columnName 
inner join Table4 tb4 on tb4.ColumnName = tb3.columnName
inner join Table5 tb5 on tb5.ColumnName = tb2.ColumnName

Answer 2

我想这就是您要找的。而且，您在 select 语句中有两次 tb4.columnName。

Select tb4.columnName As test1,
   tb2.columnName As test2,
   tb4.columnName As test3 
from [dbname].Table2 tb2
JOIN [dbname].Table5 tb5 ON tb5.ColumnName = tb2.ColumnName
JOIN Table1  tb1 ON tb2.ColumnName = tb1.ColumnName
JOIN Table3 tb3 ON tb3.ColumnName = tb1.columnName 
JOIN Table4 tb4 ON tb4.ColumnName = tb3.columnName

SQL 中未绑定的多部分标识符列

Multipart identifier column not bound in SQL

sql-server

join

multipart