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Hello,
I want to build a Body of a REST API call using M Query in PowerBI.
I have a list of ID from a list named "UserID" that I want to use it as a variable in the body
Here is my script
body = "{""ids"":" & List.Distinct(UserID) & "}",
When I executed it, it gave me an errors:
Expression.Error: We cannot apply operator & to types Text and List.
Details:
Operator=&
Left={"ids":
Right=[List]
How can I handle this error? what can be a workaround?
Thanks for your help.
Solved! Go to Solution.
@lily99 , you might want to try
body = "{""ids"":[" & Text.Combine(List.Transform(List.Distinct(UserID), each """" & _ & """"),",") & "]}"
| Thanks to the great efforts by MS engineers to simplify syntax of DAX! Most beginners are SUCCESSFULLY MISLED to think that they could easily master DAX; but it turns out that the intricacy of the most frequently used RANKX() is still way beyond their comprehension! |
DAX is simple, but NOT EASY! |
Hello @ImkeF
Thanks for your suggestion, I applied it.
body = "{""ids"":[""" & Text.Combine(List.Distinct(UserID),",") & """]}"
and get the result
{"ids":["User1,User2,User3,User4"]}
However, I want to have the result like this:
{"ids":["User1","User2","User3","User4"]}
so I applied extra "" around the list
= "{""ids"":[" & Text.Combine({"""",List.Distinct(UserID),""""},",") & "]}"
and I got this error:
Expression.Error: We cannot convert a value of type List to type Text.
Details:
Value=[List]
Type=[Type]
How can I make my body return like this?
{"ids":["User1","User2","User3","User4"]}
Thanks alot
@lily99 , you might want to try
body = "{""ids"":[" & Text.Combine(List.Transform(List.Distinct(UserID), each """" & _ & """"),",") & "]}"
| Thanks to the great efforts by MS engineers to simplify syntax of DAX! Most beginners are SUCCESSFULLY MISLED to think that they could easily master DAX; but it turns out that the intricacy of the most frequently used RANKX() is still way beyond their comprehension! |
DAX is simple, but NOT EASY! |
Hi @lily99 ,
if you want to pass a string into the body, you'd have to transform the list into a string as well. Meaning, concatenate the values by comma for example:
body = "{""ids"":" & Text.Combine(List.Distinct(UserID), ",") & "}",
Imke Feldmann (The BIccountant)
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