访问 - row_number 函数？

debugcn 发表于 Dev

安迪K

我有这个查询，它给了我想要的结果 postgres

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Access在分析函数不存在的地方翻译上面的查询......

我用这个答案来建立下面的查询

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

问题是我只有1在cnt列中。

我试图通过删除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。在cnt不断增长，但它给我的错cnt

任何帮助都非常受欢迎，因为我正在慢慢失去理智。

谢谢

编辑：请找到sqlfiddle

史蒂夫·洛弗尔

我认为 Gordon-Linoff 的代码接近你想要的，但有一些错别字我不能不重写就更正，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)子查询内，主表被带入两次。一个版本用于在您的结果中显示，另一个版本用于计算记录以生成序列号。

Gordon 说你需要为每一行一个唯一的 id 列。如果“列”的意思是还包括派生列，那就是对的。此外，它只需要在“internal_reference”和“Movement_date”的任意组合中是唯一的。

我可能错误地假设 PO_Number 就足够了。如果没有，请与该（和一些分隔符）其他字段连接，这将使其独一无二。需要对where子句进行更新，以比较t1和t2的“使此唯一的列组合”。

如果没有合适的组合可用，我不确定它可以在没有 The-Gambill 建议的 VBA 和/或临时表的情况下完成。

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