Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

Grow your Fabric skills and prepare for the DP-600 certification exam by completing the latest Microsoft Fabric challenge.

Reply
PaulDBrown
Community Champion
Community Champion

Indexing by change of row value

Hi everyone,

 

Any chance you could help with another indexing question? Basically I need to create an index which changes when the row value changes from TRUE to False and then to TRUE ect...

Here is an example:

Index Value Expected outcome
1 TRUE 1
2 TRUE 1
3 TRUE 1
4 TRUE 1
5 TRUE 1
6 FALSE 2
7 FALSE 2
8 FALSE 2
9 TRUE 3
10 TRUE 3
11 TRUE 3
12 FALSE 4
13 FALSE 4
14 FALSE 4
15 FALSE 4
16 FALSE 4
17 TRUE 5

 

Thanks in advance!





Did I answer your question? Mark my post as a solution!
In doing so, you are also helping me. Thank you!

Proud to be a Super User!
Paul on Linkedin.






1 ACCEPTED SOLUTION
Vijay_A_Verma
Super User
Super User

See the working here - Open a blank query - Home - Advanced Editor - Remove everything from there and paste the below code to test

1. If performance is not a consideration, then Group by approach

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUQoJCnVVitWJVjJC5hgjc0yQOabIHDMgx83RJxjCM0fhWaDwLJG1GRqg8FCcYWiEos/QGJVrgso1ReWiusfQHG5wLAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Index = _t, Value = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Index", Int64.Type}, {"Value", type logical}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Value"}, {{"Temp", each _, type table [Index=nullable number, Value=nullable logical]}}, GroupKind.Local),
    #"Removed Columns" = Table.RemoveColumns(#"Grouped Rows",{"Value"}),
    #"Added Index" = Table.AddIndexColumn(#"Removed Columns", "New Index", 1, 1, Int64.Type),
    #"Expanded Temp" = Table.ExpandTableColumn(#"Added Index", "Temp", {"Index", "Value"}, {"Index", "Value"})
in
    #"Expanded Temp"

2. If performance is a consideration, then List.Generate approach

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUQoJCnVVitWJVjJC5hgjc0yQOabIHDMgx83RJxjCM0fhWaDwLJG1GRqg8FCcYWiEos/QGJVrgso1ReWiusfQHG5wLAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Index = _t, Value = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Index", Int64.Type}, {"Value", type logical}}),
    ListOfValue = List.Buffer(#"Changed Type"[Value]),
    RowCount = List.Count(ListOfValue),
    GenerateIndex = List.Generate(()=>[x=1,i=0], each [i]<RowCount, each [i=[i]+1, x=if ListOfValue{i}<>ListOfValue{[i]} then [x]+1 else [x]], each [x]),
    Result = Table.FromColumns(Table.ToColumns(#"Changed Type") & {GenerateIndex},Table.ColumnNames(#"Changed Type")&{"New Index"})
in
    Result

View solution in original post

2 REPLIES 2
Vijay_A_Verma
Super User
Super User

See the working here - Open a blank query - Home - Advanced Editor - Remove everything from there and paste the below code to test

1. If performance is not a consideration, then Group by approach

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUQoJCnVVitWJVjJC5hgjc0yQOabIHDMgx83RJxjCM0fhWaDwLJG1GRqg8FCcYWiEos/QGJVrgso1ReWiusfQHG5wLAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Index = _t, Value = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Index", Int64.Type}, {"Value", type logical}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Value"}, {{"Temp", each _, type table [Index=nullable number, Value=nullable logical]}}, GroupKind.Local),
    #"Removed Columns" = Table.RemoveColumns(#"Grouped Rows",{"Value"}),
    #"Added Index" = Table.AddIndexColumn(#"Removed Columns", "New Index", 1, 1, Int64.Type),
    #"Expanded Temp" = Table.ExpandTableColumn(#"Added Index", "Temp", {"Index", "Value"}, {"Index", "Value"})
in
    #"Expanded Temp"

2. If performance is a consideration, then List.Generate approach

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUQoJCnVVitWJVjJC5hgjc0yQOabIHDMgx83RJxjCM0fhWaDwLJG1GRqg8FCcYWiEos/QGJVrgso1ReWiusfQHG5wLAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Index = _t, Value = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Index", Int64.Type}, {"Value", type logical}}),
    ListOfValue = List.Buffer(#"Changed Type"[Value]),
    RowCount = List.Count(ListOfValue),
    GenerateIndex = List.Generate(()=>[x=1,i=0], each [i]<RowCount, each [i=[i]+1, x=if ListOfValue{i}<>ListOfValue{[i]} then [x]+1 else [x]], each [x]),
    Result = Table.FromColumns(Table.ToColumns(#"Changed Type") & {GenerateIndex},Table.ColumnNames(#"Changed Type")&{"New Index"})
in
    Result

Superb. Thanks @Vijay_A_Verma !





Did I answer your question? Mark my post as a solution!
In doing so, you are also helping me. Thank you!

Proud to be a Super User!
Paul on Linkedin.






Helpful resources

Announcements
Europe Fabric Conference

Europe’s largest Microsoft Fabric Community Conference

Join the community in Stockholm for expert Microsoft Fabric learning including a very exciting keynote from Arun Ulag, Corporate Vice President, Azure Data.

Power BI Carousel June 2024

Power BI Monthly Update - June 2024

Check out the June 2024 Power BI update to learn about new features.

RTI Forums Carousel3

New forum boards available in Real-Time Intelligence.

Ask questions in Eventhouse and KQL, Eventstream, and Reflex.

Top Solution Authors
Top Kudoed Authors