How to split a CSV file into tables based on blank rows

[JollyRoger01]

I have a CSV file that has multiple tables in that are seperated vertically. I want to know how to import these into tables (preferrably in 1 or 2 steps) based on a blank (or multiple blank) row/s.

So the following:

csv.csv

2021-05-01	2021-05-02	2021-05-03	2021-05-04
Apples	Banana	Orange	Apple
Banana	Apple	Mango	Watermelon
01-04-2021	02-04-2021	03-04-2021	04-04-2021
Sunflower	Poppy	Rose	Daffodil
Lilly	Sunflower	Cornflower	Poppy

Would end up like:

Table1

2021-05-01	2021-05-02	2021-05-03	2021-05-04
Apples	Banana	Orange	Apple
Banana	Apple	Mango	Watermelon

Table2

01-04-2021	02-04-2021	03-04-2021	04-04-2021
Sunflower	Poppy	Rose	Daffodil
Lilly	Sunflower	Cornflower	Poppy

[mahoneypat]

Your two resulting tables are very similar (date headers with 1+ rows of category values).  It would probably be better to unpivot and append them to result in one table.  That will likely make your visualization/analysis easier.  Would that work?  If so, the community could suggest a specific query solution given your data.

Pat

[JollyRoger01]

I see what you mean, though unfortunately the info is unrelated and I need them all in seperate tables.

[Vera_33]

Hi @JollyRoger01 

So you have no idea how many blank rows, I have tried one way

first table

let
    Source = Csv.Document(File.Contents("C:\Users\----\Book1.csv"),[Delimiter=",", Encoding=1252, QuoteStyle=QuoteStyle.None]),
    checkBlank = Table.CombineColumns( Source, Table.ColumnNames(Source), (x)=> if List.MatchesAll(x,each _ = "") then 1 else 0,"check"),
    firstTable = Table.FirstN(Source, List.PositionOf( checkBlank[check],1,0))
in
    firstTable

second table

let
    Source = Csv.Document(File.Contents("C:\Users\----\Book1.csv"),[Delimiter=",", Encoding=1252, QuoteStyle=QuoteStyle.None]),
    checkBlank = Table.CombineColumns( Source, Table.ColumnNames(Source), (x)=> if List.MatchesAll(x,each _ = "") then 1 else 0,"check"),
    secondTable = Table.Skip(Source, List.PositionOf( checkBlank[check],1, List.Count( List.Select( checkBlank[check], each _=1))-1)+1)
in
    secondTable

[JollyRoger01]

Yes that looks like it would work, however I don't know how many blank rows and hence how many tables there will be. I have tried to index each none blank section and increment them here: How-to-increment-a-number-variable-if-column-value-equals thinking that I could somehow use this info to create indexed tables, but so far no luck. This is a common csv output format from many of the tools we use at work so I thought there would be some sort of standardised way to do this.

[Vera_33 · Accepted solution]

Hi @JollyRoger01 

I missed that multiple tables...you need to group the rows into different tables, another way of increasing index, you can take from here

let
    Source = Csv.Document(File.Contents("C:\Users\----\Book1.csv"),[Delimiter=",", Encoding=1252, QuoteStyle=QuoteStyle.None]),
    checkBlank = Table.CombineColumns(Source, Table.ColumnNames(Source), (x)=> if List.MatchesAll(x,each _ = "") then 1 else 0,"check"),
    #"Added Index" = Table.AddIndexColumn(checkBlank, "Index", 0, 1, Int64.Type),
    #"Added Custom" = Table.AddColumn(#"Added Index", "Group", each if [Index]=0 then 0 
else if [check] = 0 then List.Sum(List.FirstN( checkBlank[check], [Index])) 
else -1),
    SouceIndex = Table.AddIndexColumn(Source, "Index", 0,1),
    #"Merged Queries" = Table.NestedJoin(SouceIndex, {"Index"}, #"Added Custom", {"Index"}, "Group", JoinKind.LeftOuter),
    #"Expanded Group" = Table.ExpandTableColumn(#"Merged Queries", "Group", {"check", "Group"}, {"check", "Group"}),
    #"Filtered Rows" = Table.SelectRows(#"Expanded Group", each ([check] = 0)),
    #"Removed Columns" = Table.RemoveColumns(#"Filtered Rows",{"Index", "check"}),
    #"Grouped Rows" = Table.Group(#"Removed Columns", {"Group"}, {{"allrows", each _, type table }})
in
    #"Grouped Rows"

[JollyRoger01]

Perfect, thank you so much!

I just had one last question on this, do you know how I promote the headers of all the tables when they are grouped (from the very last step) without having to open each?

EDIT: All good, got this one worked out:

#"Promote Headers" = Table.TransformColumns(#"Grouped Rows", {{"allrows", each Table.PromoteHeaders(_, [PromoteAllScalars = true])}})
in