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aammontecas
New Member

Convert name to id for use in m query

Hello, I am using Query Parameters to format a call to an API to return data for a given trackingId.

 

I have a table with userName, trackingId. I want to call an API to populate a new table, the input to that call is trackingId

 

"https://apibaseurl.com" & "/application?trackingId=" & Uri.EscapeDataString(trackingId)"

 

I want a user to be able to enter a userName in the parameter, but have the query use the trackingId of that userName

2 REPLIES 2
aammontecas
New Member

I have created the lookup table called device containing alias(name), mac(id), and the list of alias called l_device_username, using that query I created a parameter trackingUser.

 

I added this to the query

 

#"device" = {[alias=#"trackingUser"]}[mac],
Source = Json.Document(Web.Contents("https://apibaseurl" & "/application?trackingId=" & Uri.EscapeDataString(#"device") & "&startTime=" & Uri.EscapeDataString(startTime) & "&endTime=" & Uri.EscapeDataString(endTime), [Headers=[#"Content-Type"="application/json", #"Api-Key"="*"]])),
content = Source[content],

 

But get this error:

 

Expression.Error: We cannot apply field access to the type List.
Details:
Value=[List]
Key=mac

Daryl-Lynch-Bzy
Resident Rockstar
Resident Rockstar

Hi @aammontecas 

 

I would approach this problem by creating a Table with two columns.  Name and ID.

A List of Name can be created using the "Name" column.  This List of Names can be used in the Parameter settings.  This is example from the Manage Parameters panel.

DarylLynchBzy_0-1642615899219.png

 

Finally, in the main API call, you can use the "Name" value to search for the "ID" value.  The M script is something like this:

#"Name Table"{[Name=#"Parameter Value"]}[ID]


This seraches for the Table, finds the row number for the parameter name and then returns the ID value.


 

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