Question

我有这个查询，它在postgres

上提供了所需的结果

SELECT
  t.*,
  ROW_NUMBER() OVER (PARTITION BY t."Internal_reference", t."Movement_date" ORDER BY t."Movement_date") AS "cnt"
FROM (SELECT
  "Internal_reference",
  MAX("Movement_date") AS maxtime
FROM dw."LO-D4_Movements"
GROUP BY "Internal_reference") r
INNER JOIN dw."LO-D4_Movements" t
  ON t."Movement_date" = r.maxtime
  AND t."Internal_reference" = r."Internal_reference"

问题是我必须在Access上翻译上面的查询，其中分析函数不存在...

我使用此answer构建了下面的查询

SELECT 
      t."Internal_reference",
      t.from_code,
      t.to_code,
      t."Movement_date",
      t.shipment_number,
      t."PO_number",
      t."Quantity",
      t."Movement_value",
      t."Site",
      t."Import_date",
  COUNT(*) AS "cnt"
 FROM (
      SELECT "Internal_reference",
      MAX("Movement_date") AS maxtime
      FROM dw."LO-D4_Movements"
      GROUP BY "Internal_reference") r
LEFT OUTER JOIN dw."LO-D4_Movements" t
        ON t."Movement_date" = r.maxtime AND t."Internal_reference" = r."Internal_reference"
GROUP BY
      t.from_code,
      t.to_code,
      t."Movement_date",
      t.shipment_number,
      t."PO_number",
      t."Quantity",
      t."Movement_value",
      t."Site",
      t."Import_date",
      t."Internal_reference" 
ORDER BY t.from_code

问题是我1列中只有cnt。

我尝试删除internal_reference（见下文）

来调整它

SELECT 
      t.from_code,
      t.to_code,
      t."Movement_date",
      t.shipment_number,
      t."PO_number",
      t."Quantity",
      t."Movement_value",
      t."Site",
      t."Import_date",
  COUNT(*) AS "cnt"
 FROM (
      SELECT "Internal_reference",
      MAX("Movement_date") AS maxtime
      FROM dw."LO-D4_Movements"
      GROUP BY "Internal_reference") r
LEFT OUTER JOIN dw."LO-D4_Movements" t
        ON t."Movement_date" = r.maxtime AND t."Internal_reference" = r."Internal_reference"
GROUP BY
      t.from_code,
      t.to_code,
      t."Movement_date",
      t.shipment_number,
      t."PO_number",
      t."Quantity",
      t."Movement_value",
      t."Site",
      t."Import_date" 
ORDER BY t.from_code

然而，结果更糟。 cnt正在增长，但却给了我错误的cnt

任何帮助都非常受欢迎，因为我慢慢失去理智。

谢谢

修改：请找到sqlfiddle

Answer 1

我认为Gordon-Linoff的代码接近你想要的，但有一些错字我无法改写而没有重写，所以这是我的尝试

SELECT
    t1.Internal_reference,
    t1.Movement_date,
    t1.PO_Number as Combination_Of_Columns_Which_Make_This_Unique,
    t1.Other_columns,
    Count(1) AS Cnt
FROM
    ([LO-D4_Movements] AS t1
    INNER JOIN [LO-D4_Movements] AS t2 ON
        t1.Internal_reference = t2.Internal_reference AND
        t1.Movement_date = t2.Movement_date)
    INNER JOIN (
        SELECT
            t3.Internal_reference,
            MAX(t3.Movement_date) AS Maxtime
        FROM
            [LO-D4_Movements] AS t3
        GROUP BY
            t3.Internal_reference
            )  AS r ON
        t1.Internal_reference = r.Internal_reference AND
        t1.Movement_date = r.Maxtime
WHERE  
    t1.PO_Number>=t2.PO_Number
GROUP BY
    t1.Internal_reference,
    t1.Movement_date,t1.PO_Number,
    t1.Other_columns
ORDER BY
    t1.Internal_reference,
    t1.Movement_date,
    Count(1);

除了max(movement_date)子查询中，主表还会被引入两次。一个版本是用于显示结果的版本，另一个版本用于计算记录以生成序列号。

戈登说你需要为每一行提供一个唯一的id列。如果通过＆＃34;列＆＃34;这是真的。你的意思是包括派生列。此外，它只需要在＆＃34; internal_reference＆＃34;的任何组合中都是唯一的。和＆＃34; Movement_date＆＃34;。

我认为，或许是错误的，PO_Number就足够了。如果没有，请与其他字段（以及一些分隔符）连接，使其成为唯一的字段。 where子句需要更新以比较t1和t2的＆＃34;列的组合，这使得这个唯一的＆＃34;。

如果没有合适的组合，我不确定如果没有VBA和/或临时表，可以像The-Gambill建议的那样完成。

Answer 2

据我所知，这是MS Access的真正痛苦。一种方法是相关子查询，但每行需要一个唯一的id列：

SELECT t.*,
       (SELECT COUNT(*)
        FROM (SELECT "Internal_reference", MAX("Movement_date") AS maxtime
              FROM dw."LO-D4_Movements"
              GROUP BY "Internal_reference"
             ) as t2
        WHERE t2."Internal_reference" AND t."Internal_reference" AND

              t2."Movement_date" = t."Movement_date" AND
              t2.?? <= t.??
       ) as cnt
FROM (SELECT "Internal_reference", MAX("Movement_date") AS maxtime
      FROM dw."LO-D4_Movements"
      GROUP BY "Internal_reference"
     ) r INNER JOIN
     dw."LO-D4_Movements" t
     ON t."Movement_date" = r.maxtime AND
        t."Internal_reference" = r."Internal_reference";

??用于id或创建日期或允许计算行的东西。

access - row_number函数？

2 个答案: