使用公用表表达式时出现“语法错误”

Question

WITH list_dedup (Company, duplicate_count) AS
(
     SELECT
         *,
         ROW_NUMBER() OVER (PARTITION BY Company ORDER BY Email) AS 'RowNumber'
     FROM
         Travels
)

错误：

消息 102，第 15 级，状态 1，第 7 行
')' 附近的语法不正确。

Answer 1

您缺少公共表表达式的最终选择（在 CTE 的定义之后）：

WITH list_dedup  (Company,duplicate_count) As
(
  select *,
         ROW_NUMBER() OVER (PARTITION BY Company ORDER by Email) As "RowNumber"
  From Travels
)
select *  
from list_dedup;

但这不会，因为 CTE 被定义为具有两列（通过

WITH list_dedup  (Company,duplicate_count)

），但您在 CTE 内的选择返回至少三列（公司、电子邮件、行号）。您需要调整 CTE 的列定义，或者完全忽略它：

WITH list_dedup As
(
  select *,
         ROW_NUMBER() OVER (PARTITION BY Company ORDER by Email) As "RowNumber"
  From Travels
)
select *  
from list_dedup;

---

当定义列列表时，内部选择中的

As "RowNumber"

也没有意义，因为 CTE 定义定义了列名称。在 CTE 内部使用的任何别名在其外部都将不可见（如果在

with .. (...) as

部分中指定了 CTE 列）。

Answer 2

您刚刚设置您的 CTE - 现在您需要使用它！

WITH list_dedup (Company, duplicate_count) AS
(
     SELECT
         *,
         ROW_NUMBER() OVER (PARTITION BY Company ORDER BY Email) AS 'RowNumber'
     FROM
         Travels
)
SELECT *
FROM list_dedup

Answer 3

;WITH list_dedup (Company, duplicate_count) AS
(
     SELECT
         *,
         ROW_NUMBER() OVER (PARTITION BY Company ORDER BY Email) AS 'RowNumber'
     FROM
         Travels
)

SELECT * FROM list_dedup