Append queries based on excel cell values.

[MohsinBipu]

I have some queries and I append all queries into a Master query.

SS23_LL_LP + AH23_LL_LP + SS24_LL_LP = MasterChartLL

But I want that MasterChartLL will be appended based on the Excel table. 

My requirement: 

I have an excel table like the below picture.

If the Excel chart is updated SS23, AW23 then, 

MasterChartLL will append SS23_LL_LP + AH23_LL_LP

Or

If In Excel chart, is updated with SS23, and SS24 then, 

MasterChartLL will append SS23_LL_LP + SS24_LL_LP

How can I dynamic append queries based on excel data? 

[ams1 · Accepted solution]

Hi @MohsinBipu 

They say "eval is EVIL", but in PowerQuery it's an angel 👼!

Given:

...and TLSeasonFilter is:

WHEN MasterChartLL is:

let
    Source = TLSeasonFilter,
    #"Added WithSuffix" = Table.AddColumn(Source, "WithSuffix", each [Season] & "_LL_SP"),
    //                                                                          ^^^^^^^^ - all have same suffix, right?
    #"Removed Other Columns" = Table.SelectColumns(#"Added WithSuffix", {"WithSuffix"}),
    TableToList = Table.ToList(#"Removed Other Columns"),
    listOfTables = List.Accumulate(
        TableToList, {}, (final, current) => List.Combine({final, {Expression.Evaluate(current, #shared)}})
    ),
    ret = Table.Combine(listOfTables) // assumes all tables have same header
in
    ret

Then you should get what you want - if I understood it correctly. 😉

Please mark this as ANSWER if it helped.

P.S.: currently the TLSeasonFilter controls what tables get appended. If you want SS24_LL_LP to be always present, just add it to the List.Accumulate seed: instead of "{}", use "{Expression.Evaluate("SS24_LL_SP", #shared)}"

[MohsinBipu]

From this step, this is not working. Before, all steps are working. I think, Need to change something. Please advise. Not an expert in M language. 😞 

[ams1]

Hi @MohsinBipu 

Can you please share the error?

[MohsinBipu]

Ohhh, Sorry, My mistake. I have found the reason.  Basically, I update the excel wrong and There are no Power query exists. that's why This error is coming. Anyhow, can I avoid this error with  formula update, like if no query exists as per the excel update, then the formula will avoid those query?

[ams1]

Hi @MohsinBipu 

First of all, if it worked and it helped, please mark my first reply as answer 🤗. 

Second, I think you can put a "try" before Expression.Evaluate... and after an "otherwise null" - and see if it works.

[MohsinBipu]

something like below?

let
    Source = TLSeasonFilter,
    #"Added WithSuffix" = Table.AddColumn(Source, "WithSuffix", each [Season] & "_LL_SP"),
    //                                                                          ^^^^^^^^ - all have same suffix, right?
    #"Removed Other Columns" = Table.SelectColumns(#"Added WithSuffix", {"WithSuffix"}),
    TableToList = Table.ToList(#"Removed Other Columns"),
    listOfTables = List.Accumulate(
        TableToList, {}, (final, current) => List.Combine({final, {try Expression.Evaluate(current, #shared)} otherwise null})
    ),
    ret = Table.Combine(listOfTables) // assumes all tables have same header
in
    ret

[ams1]

Hi @MohsinBipu 

Something like:

let
    Source = TLSeasonFilter,
    #"Added WithSuffix" = Table.AddColumn(Source, "WithSuffix", each [Season] & "_LL_SP"),
    //                                                                          ^^^^^^^^ - all have same suffix, right?
    #"Removed Other Columns" = Table.SelectColumns(#"Added WithSuffix", {"WithSuffix"}),
    TableToList = Table.ToList(#"Removed Other Columns"),
    listOfTables = List.Accumulate(
        TableToList, {}, (final, current) => List.Combine({final, {try Expression.Evaluate(current, #shared) otherwise null}})
    ),
    ret = Table.Combine(listOfTables) // assumes all tables have same header
in
    ret