List.Generate calling outside function

[MatheusLPS]

Hello,

I made a recursion function with List.Generate. It is working. My question is related the performance.

My goal is to see on a tree the master brach from inner levels. 

My function looks like below. Comments and question on the code.

let

	search_area  = (area_param) =>  //outside parameter from column table

	let
		Source = (id_param as number) =>
		let
			table_result = Sql.Database("my server", "my data base", [Query="My select query with parameter" & Number.ToText(id_param), CreateNavigationProperties=false]),
		in
		table_result,

		areas_function = List.Generate 
		(
			() => [area_id_f = area_param, name_f = "xx", parent_id_f = 1], //inicital values. Just anything
			each [parent_id_f] <> null,                                     //while my flag is not null
			each                                                            //my question is here. To update my variables, I am calling the outside "Source" function each time. Is it correct?
			[
				area_id_f  = Source([area_id_f]){0}[parent_id],
				name_f = Source([area_id_f]){0}[name],
				parent_id_f = Source([area_id_f]){0}[parent_id]
			],
			each [name_f]                //When my flag is null, return the master branch name
		),

		areas_geradas =  List.Last(areas_function)     //Just the last one
	in
	areas_geradas

in search_area

[v-yulgu-msft]

Hi @MatheusLPS,

Some experts being experienced in Power Query might provide professional advice for you.

@ImkeF, @MarcelBeug, Do you have any comment to this topic? appreciate for your help.

Thanks,

Yuliana Gu

[ImkeF]

Sorry @MatheusLPS, but I cannot follow you here.

Could you please post a link to a sample file where I can follow what you're trying to achieve?

Thanks.