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I use the Json.Document(Web.Contents(....)) to request data. I created a function where I can extract the information for a single project using [projNo]="01"
I have a separate table with the column [projNo]. I want to use the value in this column to extract the information for all of the projects.
Here is my function getProjectURI()
(ProjectNo as text, tblColumn as table)=>
let
#"FilterColumnTable" = Table.SelectRows(tblColumn, each Record.Field(_,ProjectNo)),
DatabaseName = "abc",
ObjectType = "rooms",
Proj =
Json.Document(
Web.Contents(
"https://api-us.drofus.com/api/",
[
RelativePath= DatabaseName & "/" & ProjectNo & "/" & ObjectType & "?$select=room_function_0_no,room_function_0_name,room_function_1_no,room_function_1_name,room_func_no,name,description,architect_no,programmed_area,designed_area,rds_status"
]
)
)
in
Proj
This function works fine as = getProjectURI("01", #"000Projects")
But when I add the function as a step in the Projects table I get the error Expression.Error: The name '_" wasn't recognized.
= getProjectURI(Record.Field(_, [projNo]), Source)
I don't know where to place the Record.Field(_, [projNo]) in the function.
Thank you for any suggestions.
Solved! Go to Solution.
Thank you @latimeria, I figured out my issue. I was calling my function incorrectly!
Instead, I needed to Invoke Custom Function (Add Column tab) to call the function.
This is my solution:
= Table.AddColumn(Source, "getProjectURI", each getProjectURI([projNo], "rooms", #"101mapRooms"))
I had tried to simplify the function but eliminated a key component as you noted:
#"FilterColumnTable"
Thank you for your patience. I am learning slowly.
The correct function is this:
(ProjectNo as text, ObjectType as text, tblColumn as table) =>
let
#"FilterColumnTable" = Table.SelectRows(tblColumn, each ([ObjectType] = ObjectType)),
DatabaseName = "abc",
Proj =
Json.Document(
Web.Contents(
"https://api-us.drofus.com/api/",
[
RelativePath = DatabaseName & "/" & ProjectNo & "/" & ObjectType & "?$select=" & Text.Combine(#"FilterColumnTable"[dRofus.ID], ",")
]
)
)
in
Proj
This function requires two tables. Table1 invokes the function and has the index [projNo]. Table2 is the lookup (mapping) table that stores all of the fields for the API call. Table2 is referenced in the #"filterColumnTable"
Thank you @latimeria, I figured out my issue. I was calling my function incorrectly!
Instead, I needed to Invoke Custom Function (Add Column tab) to call the function.
This is my solution:
= Table.AddColumn(Source, "getProjectURI", each getProjectURI([projNo], "rooms", #"101mapRooms"))
I had tried to simplify the function but eliminated a key component as you noted:
#"FilterColumnTable"
Hello @MarkusEng1998 ,
try by replacing _ with r
#"FilterColumnTable" = Table.SelectRows(tblColumn,(r)=> Record.Field(r,ProjectNo)),
(ProjectNo as text, tblColumn as table)=>
let
// #"FilterColumnTable" = Table.SelectRows(tblColumn, each Record.Field(_,ProjectNo)),
#"FilterColumnTable" = Table.SelectRows(tblColumn, (r) => Record.Field(r,ProjectNo)),
DatabaseName = "abc",
ObjectType = "rooms",
Proj =
Json.Document(
Web.Contents(
"https://api-us.drofus.com/api/",
[
RelativePath= DatabaseName & "/" & ProjectNo & "/" & ObjectType & "?$select=room_function_0_no,room_function_0_name,room_function_1_no,room_function_1_name,room_func_no,name,description,architect_no,programmed_area,designed_area,rds_status"
]
)
)
in
Proj
Expression.Error: There is an unknown identifier. Did you use the [field] shorthand for a _[field] outside of an 'each' expression?
Am I missing the 'each'
Hi @MarkusEng1998 ,
Sorry, I misunderstood the issue.
Call the function like this: getProjectURI([projNo], Source)
My understanding is that the step #"FilterColumnTable" is useless
#"FilterColumnTable" = Table.SelectRows(tblColumn, (r) => Record.Field(r,ProjectNo)),
you select no row (no condition).
FYI , each is a shortcut for the function (_)=> .
If it doesn't work, can you provide an example of the whole step when calling the function.
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