Forum Discussion
How do I make this loop all children recursively?
Hello guys, i have a function ("flecheD")
(ColChild,ColParent,ParentActuel,source)=>
let
mylist=Table.Column(Table.SelectRows(source,each Record.Field(_,ColParent)=ParentActuel),ColChild),
resultat=Text.Combine(mylist)
in
Text.Trim(
if resultat ="" then "" else @ resultat &"|" & @ flecheD(ColChild,ColParent,resultat,source),"|")which loops through 2 columns (Parent,Child) to get all children of the main parent (output->Children column). The problem is that when the function is confronted with several children, the result variable no longer has a single letter/child but several, which blocks the function from looking for the other children. Can you help me to solve this problem thanks,
Anonymous
Please try this function. Seems to be do what you are looking for.
(inputtable as table, searchvalue as text, inputtext as text)=> let input = searchvalue, childrows = try Table.SelectRows(inputtable, each [Parent] = input)[Child] otherwise {}, output = if List.IsEmpty(childrows) then inputtext & Text.Combine(childrows, "") else Text.Combine(childrows, "") & Text.Combine(List.Transform(childrows, each @fnParentChild(inputtable, _, "")), "|") in outputIf needed, you can see it with your data, you can put this in a blank query.
let Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WclTSUXIC4oAgfxcQ08s5VClWJ1rJGchxQYi71HiChUHKvbAo98Kt3BmLcpB4KBZxEMcTIQ40JBYA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Parent = _t, Child = _t, Param = _t, Children = _t]), #"Changed Type" = Table.TransformColumnTypes(Source,{{"Parent", type text}, {"Child", type text}, {"Param", type text}, {"Children", type text}}), #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each let par = [Parent] in fnParentChild(#"Changed Type", par, "")) in #"Added Custom"Pat
3 Replies
- ppm1Solution Sage
Please try this function. Seems to be do what you are looking for.
(inputtable as table, searchvalue as text, inputtext as text)=> let input = searchvalue, childrows = try Table.SelectRows(inputtable, each [Parent] = input)[Child] otherwise {}, output = if List.IsEmpty(childrows) then inputtext & Text.Combine(childrows, "") else Text.Combine(childrows, "") & Text.Combine(List.Transform(childrows, each @fnParentChild(inputtable, _, "")), "|") in outputIf needed, you can see it with your data, you can put this in a blank query.
let Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WclTSUXIC4oAgfxcQ08s5VClWJ1rJGchxQYi71HiChUHKvbAo98Kt3BmLcpB4KBZxEMcTIQ40JBYA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Parent = _t, Child = _t, Param = _t, Children = _t]), #"Changed Type" = Table.TransformColumnTypes(Source,{{"Parent", type text}, {"Child", type text}, {"Param", type text}, {"Children", type text}}), #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each let par = [Parent] in fnParentChild(#"Changed Type", par, "")) in #"Added Custom"Pat
- v-yanjiang-msftCommunity Support
Hi Anonymous ,
Please see if this document can help: Loops in Power Query M language (potyarkin.ml)
Best Regards,
Community Support Team _ kalyj- AnonymousNot applicable
Hi v-yanjiang-msft , thx for your suggestion. So I tried to create a custom function "SubChilldren" with List.Generate()
(children as text, ColChild,ColParent,source)=> let i = 1, length = Text.Length(children), subchildren = List.Generate( ()=>@flecheD(ColChild,ColParent,Text.At(children,i-1),source), i<=length, i+1 ) in Text.Combine(subchildren)which when coupled with my initial function
(ColChild,ColParent,ParentActuel,source)=> let mylist=Table.Column(Table.SelectRows(source,each Record.Field(_,ColParent)=ParentActuel),ColChild), resultat=Text.Combine(mylist) in Text.Trim( if resultat ="" then "" else if Text.Length(resultat) = 1 then @ resultat &"|" & @ flecheD(ColChild,ColParent,resultat,source) else @resultat &"|"& SubChildren(resultat,ColChild,ColParent,source),"|")should normally get the sub-children of each children. However, it still doesnt work 😅. Could you please help me . Thx
@Gop01