Transform Data - add a column count based on another table

[marktait]

Hi.

I have a table "DeviceList (2)" which has a column, [Device Name].

I would like (in Transform Data -> Add New Column) to look for the "Device List (2)"[Device Name] within the "Defender SNOW"[Short description] field and count how many results it finds.

The formula below is accepted in the Custom Column editor - but then shows as an error when viewing the table in PBI (see screenshot below the formula).

Any ideas what I may be doing wrong?

Thanks for any help,

Mark

if List.IsEmpty(
        Table.SelectRows(
            #"Defender SNOW",
            (row) => Text.Contains(row[Short description], #"DeviceList (2)"[Device Name])
        )
    ) then 0
    else List.Count(
        Table.SelectRows(
            #"Defender SNOW",
            (row) => Text.Contains(row[Short description], #"DeviceList (2)"[Device Name])
        )
    )

[nsexton12]

If you click on the cell with one of the errors, what does the error message say? If you click in the grey area beside the "Error" hyperlink, it should show at the bottom of the screen.

[marktait]

Hi - it says: 

Expression.Error: A cyclic reference was encountered during evaluation.

(I assume this is similar to a circular reference - but I can't see why).

Thanks, Mark

[nsexton12]

Thank you! Could you post the full Calculated column code? 

[marktait]

Hi - yes: 

= if List.IsEmpty(
        Table.SelectRows(
            #"Defender SNOW",
            (row) => Text.Contains(row[Short description], #"DeviceList (2)"[Device Name])
        )
    ) then 0
    else List.Count(
        Table.SelectRows(
            #"Defender SNOW",
            (row) => Text.Contains(row[Short description], #"DeviceList (2)"[Device Name])
        )
    )

[nsexton12 · Accepted solution]

I think I have figured out your issue. It looks like you did not need the list functions as you could do the operations on the tables themselves. I think using the List function is what was causing the cyclical reference because as soon as I removed them they went away. Please see code below that I think solves your issue: 

if Table.RowCount(Table.SelectRows(
#"Defender SNOW",
(row) => Text.Contains( row[Short description],[Device Name])
)) = 0
then 0
else Table.RowCount(Table.SelectRows(
#"Defender SNOW",
(row) =>Text.Contains( row[Short description],[Device Name])
))

If anyone else can provide a more techincal explanation for why this caused a cyclical reference, please feel free to add on. 

Please mark as a solution if this worked for you!

[marktait]

Hi - thank you so much - it does indeed work - although I have no explanation for it either 🙂

Cheers, Mark