合并日期匹配的查询，如果找不到匹配项则保留 null

Question

下面有两个table（例子）：

Table SFID

Sales Force ID	Type	Name	Assistant	From	To
123	ABC	Store A	Ben	01/04/2020	30/04/2020
123	ABC	Store A	Jen	01/05/2020	31/05/2020
123	ABC	Store A	Ben	01/06/2020	21/06/2020
126	DEF	Store B	Tim	01/04/2020	30/04/2020
126	DEF	Store B	Tim	01/04/2020	null

和

Table Activity

Transaction ID	Date	Sales Force ID
1	03/05/2020	123
2	03/06/2020	200
3	01/01/2021	123
4	02/01/2021	126

我希望我的最终结果是

Transaction ID	Date	Sales Force ID	Type	Name	Assistant
1	03/05/2020	123	ABC	Store A	Jen
2	03/06/2020	200	null	null	null
3	01/01/2021	123	null	null	null
4	02/01/2021	126	DEF	Store B	Tim

为此，最好的解决方案是 with some modifications (allow both To and From to be null). However, only the row on transaction ID 2 disappears because that Sales Force had already had assistant entries (they get wiped out on the filtered row step). I also tried the solution presented in 中发布的解决方案，但加载需要很长时间。

我想知道是否有一种方法可以保证所有交易都出现，而不必在没有助手的情况下向 table SFID 引入行，并且不会使查询变得非常慢。

这是我的代码：

    let
    Source = Source,
    #"Merged Queries" = Table.NestedJoin(Source,{"Sales Force ID"},SFID,{"SFID"},"SFID",JoinKind.LeftOuter),
    #"Expanded SFID" = Table.ExpandTableColumn(#"Merged Queries", "SFID", {"Type", "Name", "Assistant", "From", "To"}, {"Type", "Name", "Assistant", "From", "To"}),
    #"Changed Type" = Table.TransformColumnTypes(#"SFID",{{"Date", type date}, {"From", type date}, {"To", type date}}),
    FilteredRows = Table.SelectRows(#"Changed Type", each ([Date] >= [From] and [Date] <= [To]) or ([Date] >= [From] and [To] = null)or ([From] = null and [To] = null)),
    #"Removed Columns" = Table.RemoveColumns(FilteredRows,{"From", "To"})
in
    #"Removed Columns"

Answer 1

所以在将近 2 周没有任何回应和不合理的降级之后，我找到了解决方案！

我创建了一个查询，基本上可以使用上述代码生成此 table。

Transaction ID	Date	Assistant
1	01/01/2021	Jen
4	02/01/2021	Tim

let
    Source = Source,
    #"Merged Queries" = Table.NestedJoin(Source,{"Sales Force ID"},SFID,{"SFID"},"SFID",JoinKind.LeftOuter),
    #"Expanded SFID" = Table.ExpandTableColumn(#"Merged Queries", "SFID", {"Type", "Name", "Assistant", "From", "To"}, {"Type", "Name", "Assistant", "From", "To"}),
    #"Changed Type" = Table.TransformColumnTypes(#"Expanded SFID",{{"Date", type date}, {"From", type date}, {"To", type date}}),
    FilteredRows = Table.SelectRows(#"Changed Type", each ([Date] >= [From] and [Date] <= [To]) or ([Date] >= [From] and [To] = null)),
    #"Removed Columns" = Table.RemoveColumns(FilteredRows,{"From", "To"})
in
    #"Removed Columns"

并在我的初始版本 Table Activity

中左加入它

我将 Type 和 Name 类型的信息保存在一个单独的查询中（因为它们不会改变），然后在 Table Activity 上再次左连接它.

最终查询如下所示：

let
    Source = Source,
    #"Merged Queries1" = Table.NestedJoin(Source,{"Sales Force Code"},Info,{"SFID"},"Info",JoinKind.LeftOuter),
    #"Expanded Info" = Table.ExpandTableColumn(#"Merged Queries1", "Info", {"Type", "Name"}, {"Type", "Name"}),
    #"Merged Queries" = Table.NestedJoin(#"Expanded Info",{"ID"},IDvsAssistant,{"ID"},"IDvsAssistant",JoinKind.LeftOuter),
    #"Expanded IDvsAssistant" = Table.ExpandTableColumn(#"Merged Queries", "IDvsAssistant", {"Assistant"}, {"Assistant"})
in
    #"Expanded IDvsAssistant"

合并日期匹配的查询，如果找不到匹配项则保留 null

Merge queries matching on dates and leave null if no match found

merge

m

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