Question

我正在为产品的位置制定一个定义的案例，然后希望稍后将该案例作为值返回。但是，我收到错误“'字段列表'中的未知列位置。”

SELECT location, avg(pcnt), max(pcnt), min(pcnt)
  FROM (
    -- create temporary table 'a' to serve data from inner typing table created below
    SELECT a.date_key, a.num_snowflakes/k.tot_snowflakes AS pcnt
      FROM (
        SELECT 
          date_key,
          CASE
            WHEN location_type_key=2 then 'at_customer' 
            WHEN location_type_key IN (1,13) then 'on_floor' 
            WHEN location_type_key IN (6,7,11) then 'sat1'
            WHEN location_type_key IN (4,5) then 'film'
            WHEN location_type_key IN (8,9) then 'repair'
            WHEN location_type_key IN (12) then 'inspection'
            WHEN location_type_key IN (2) then 'outside' 
            ELSE NULL END AS location,
          COUNT(distinct garment_key) AS num_snowflakes, 
          COUNT(distinct product_key) AS num_skus

          FROM database
          -- excluding vendor return and retired
            WHERE location_type_key NOT IN (3,10)
            -- between 6/15/13 and 8/15/13
              AND date_key >= 20130615 AND date_key <= 20130815
          -- aggregates by day and location case    
          GROUP BY date_key, location
        ) AS a
        JOIN 
        -- create temporary table 'k' to serve 'tot_snowflakes' to table 'a' above
          (SELECT b.date_key, sum(b.num_snowflakes) AS tot_snowflakes 
              FROM (
                SELECT 
                  date_key, 
                  CASE   
                    WHEN location_type_key=2 then 'at_customer' 
                    WHEN location_type_key IN (1,13) then 'on_floor' 
                    WHEN location_type_key IN (6,7,11) then 'sat1'
                    WHEN location_type_key IN (4,5) then 'film'
                    WHEN location_type_key IN (8,9) then 'repair'
                    WHEN location_type_key IN (12) then 'inspection'
                    WHEN location_type_key IN (2) then 'outside' 
                    ELSE NULL END AS location,
                  COUNT(distinct garment_key) AS num_snowflakes, 
                  COUNT(distinct product_key) AS num_skus

                  FROM database
                    WHERE location_type_key NOT IN (3,10)
                    -- between 6/15/13 and 8/15/13
                      AND date_key >= 20130615 AND date_key <= 20130815
                  -- aggregates by day and location case    
                  GROUP BY date_key, location
                ) AS b
            ) AS k
          ON a.date_key=k.date_key
      GROUP BY a.date_key, a.location
    ) AS z

我试图确保我总是调用正确的表格，所以我不确定错误来自哪里。有人有什么想法吗？

谢谢！

Answer 1

您最外面的查询SELECTs FROM table z。

表z源自SELECT FROM表和JOIN表k。

表a派生自SELECT FROM表“database”。

表k派生自SELECT FROM派生表b。

表b派生自SELECT FROM基表“database”。

这里的简短回答是，您的查询的第一行实际上是在询问：

SELECT z.location, avg(z.pcnt), max(z.pcnt), min(z.pcnt)

派生表z只有两列，“date_key”和“pcnt”。

(SELECT a.date_key, a.num_snowflakes/k.tot_snowflakes AS pcnt
...
) AS z

要使查询起作用，表z需要一个位置，该位置必须在每个嵌套选择中都是显式的，直到您可以将其追溯到您想要实际读取它的基表。

看起来对于你想要完成的结果来说，查询的工作量超过了必要的工作量，但我一直盯着它，直到我的眼睛失去了专注的能力，所以我会坚持目前这个答案：每个需要将其“位置”列向上渗透到最外层选择的派生表需要明确地选择它。

调用[MySQL]时定义的大小写返回“未知列”

1 个答案: