SELECT 语句中的 SQL 2008 R2 CTE 语法错误

Question

这个问题是基于我之前的问题

SQL server 2008 R2, select one value of a column for each distinct value of another column

关于 SQL Server 2008 上的 CTE。

   WITH my_cte(id_num, rn) AS (
      SELECT name, 
      rn = ROW_NUMBER() OVER (PARTITION BY a.name ORDER BY newid())
            FROM my_table as a
      )
   SELECT id_num FROM my_cte WHERE rn = 1

   INSERT INTO #temp_table 
   SELECT a.address from another_table as a,
            id_num from my_cte  -- here, I got error!!!

为什么会出错：关键字“from”附近的语法不正确。

我需要获取一个新表，其中一列来自 another_table，一列来自 my_cte。

例如

 address (from another_table)    id_num (from my_cte)
  city_1                        65 
  city_1                        36
  city_2                        65
  city_2                        36
  city_3                        65
  city_3                        36

我应该使用什么样的连接来获取上表，以便每个地址都与 CTE 中的所有 id_num 相关联？假设 id_num 只有 65 和 36 两个值。 my_cte 没有地址列。

任何帮助将不胜感激。

Answer 1

CTE 只能用于紧跟其后的语句中。执行SELECT id_num FROM my_cte WHERE rn = 1 后，cte 不再存在。

Answer 2

CTE 仅针对单个查询存在。但是您可以将它与insert 以及select 一起使用：

   WITH my_cte(id_num, rn) AS (
      SELECT name, ROW_NUMBER() OVER (PARTITION BY a.name ORDER BY newid()) as rn
      FROM my_table as a
   )
   INSERT INTO #temp_table 
       SELECT a.address, id_num
       from another_table as a JOIN
            my_cte
            on a.name = my_cte.name;