Forum Discussion

OneWithQuestion's avatar
OneWithQuestion
Post Prodigy
3 years ago
Solved

How can I split a text string and reverse the order it splits (so first comes out last)?

I have data as shown in the first column "CurrentInput" what I want to do is split it, but I need to flip around the order first as shown in "Flipped". I can't find a good way to do this. I tri...
Need Help
  • AlienSx's avatar
    AlienSx
    3 years ago

    Hello, OneWithQuestion 

    let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwMtI1MNQJTsxJLdYJLskvSrU0MtUJSk3PzM8zVIrVgSkxQlZiYWoCVWKEpMQUWYmRsSkWJSgWGQC5ECXGSrGxAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [CurrentInput = _t]),
    column_names = { "Date", "Category", "Store", "Region" },
    output_goal = 
        Table.ReorderColumns(
            Table.FromRows(
                List.Transform(
                    Source[CurrentInput],
                    Splitter.SplitTextByDelimiter(",")
                ),
                column_names
            ),
            List.Reverse(column_names)
            
        )
in
    output_goal
  • AlienSx's avatar
    AlienSx
    3 years ago

    no. It won't work. To retain all other columns lets transform column items to list >> list reverse >> list to record with known names and finally expand this column of records.  

     

    let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwMtI1MNQJTsxJLdYJLskvSrU0MtUJSk3PzM8zVNJRSgTiVKVYHZhSI2SlFqYmUKVGQGVJQJyGpNQUWamRsSmS0mQgTkdSiuIAAyAXotQYqCwFiDOUYmMB", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [CurrentInput = _t, other_column01 = _t, other_column02 = _t]),
    column_names = { "Region", "Store", "Category", "Date"  },
    output_goal = 
        Table.ExpandRecordColumn(
            Table.TransformColumns(
                Source, 
                {
                    {"CurrentInput",
                    (x) => 
                        Record.FromList(
                            List.Reverse(
                                Splitter.SplitTextByDelimiter(",")(x)
                            ),
                            column_names
                        )
                    }
                }
            ),
            "CurrentInput",
            column_names
        )
in
    output_goal

     

     

OneWithQuestion's avatar
OneWithQuestion
Post Prodigy
3 years ago

Thank you so much!

I'm trying to properly understand this and adapt it.

I'm running into an issue with retaining existing columns in the table.

If in the example I provided, I wanted to only split the first column (which you did) but KEEP those other columns in the table, how does the syntax work for that?

How can you use Table.ReorderColumns to only address specific columns instead of the entire table?

AlienSx's avatar
AlienSx
Super User
3 years ago

no. It won't work. To retain all other columns lets transform column items to list >> list reverse >> list to record with known names and finally expand this column of records.  

 

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwMtI1MNQJTsxJLdYJLskvSrU0MtUJSk3PzM8zVNJRSgTiVKVYHZhSI2SlFqYmUKVGQGVJQJyGpNQUWamRsSmS0mQgTkdSiuIAAyAXotQYqCwFiDOUYmMB", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [CurrentInput = _t, other_column01 = _t, other_column02 = _t]),
    column_names = { "Region", "Store", "Category", "Date"  },
    output_goal = 
        Table.ExpandRecordColumn(
            Table.TransformColumns(
                Source, 
                {
                    {"CurrentInput",
                    (x) => 
                        Record.FromList(
                            List.Reverse(
                                Splitter.SplitTextByDelimiter(",")(x)
                            ),
                            column_names
                        )
                    }
                }
            ),
            "CurrentInput",
            column_names
        )
in
    output_goal