Question

我尝试使用Power Query / PowerBI加入2个表：Absence和dimDate以创建下面的结果表：

缺席表

+------------+--------------+--------------+-----------+-----------+
| EmployeeId | EmployeeName | AbsenceType  | StartDate |  EndDate  |
+------------+--------------+--------------+-----------+-----------+
|          1 | A            | Annual Leave | 2/01/2017 | 5/01/2017 |
|          2 | B            | Sick Leave   | 4/01/2017 | 6/01/2017 |
+------------+--------------+--------------+-----------+-----------+

dimDate表

+------------+
|  FullDate  |
+------------+
| 1/01/2017  |
| 2/01/2017  |
| 3/01/2017  |
| 4/01/2017  |
| 5/01/2017  |
| 6/01/2017  |
| 7/01/2017  |
| 8/01/2017  |
| 9/01/2017  |
| 10/01/2017 |
+------------+

结果

+------------+--------------+--------------+-----------+
| EmployeeId | EmployeeName | AbsenceType  |   Date    |
+------------+--------------+--------------+-----------+
|          1 | A            | Annual Leave | 2/01/2017 |
|          1 | A            | Annual Leave | 3/01/2017 |
|          1 | A            | Annual Leave | 4/01/2017 |
|          1 | A            | Annual Leave | 5/01/2017 |
|          2 | B            | Sick Leave   | 4/01/2017 |
|          2 | B            | Sick Leave   | 5/01/2017 |
|          2 | B            | Sick Leave   | 6/01/2017 |
+------------+--------------+--------------+-----------+

我通常使用SQL来创建此结果，但我不知道如何在PowerQuery中有效地执行此操作。

SELECT A.EmployeeId
        ,A.EmployeeName
        ,A.AbsenceType
        ,D.FullDate
FROM Absence AS A
INNER JOIN dimDate AS D ON (
                D.FullDate >= A.StartDate
                AND D.FullDate <= A.EndDate
                )

注意：我已经尝试了2个表之间的完全连接缺勤和dimDate，然后如果 dimDate.FullDate＆gt; = StartDate 和 dimDate.FullDate＆lt; = EndDate 。但是这种方法对于大表来说似乎无效，并且它在过滤之前会创建冗余记录，所以它很慢。

请给我一些建议。

Answer 1

无需合并。您可以创建一个列，其中包含StartDate和EndDate之间所有日期的嵌入列表。然后扩展该列。

let
    Source = Table1,
    #"Added Custom" = Table.AddColumn(Source, "Date", each List.Dates([StartDate],1+Duration.Days([EndDate]-[StartDate]),#duration(1,0,0,0))),
    #"Expanded Date" = Table.ExpandListColumn(#"Added Custom", "Date"),
    #"Changed Type" = Table.TransformColumnTypes(#"Expanded Date",{{"Date", type date}}),
    #"Removed Columns" = Table.RemoveColumns(#"Changed Type",{"StartDate", "EndDate"})
in
   #"Removed Columns"

PowerQuery PowerBI根据StartDate和EndDate之间的条件合并2个表

1 个答案: