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eyaskelani
Advocate I
Advocate I

Nested Tables duplicated rows through JSON

Hi All, 

 

I have connected a JSON web api to power BI, and i have 20 records that i imported. each record contains (columns) of First name, lead id, created time. each row has a table.

 

If i expand the first column, i get 20 rows. perfect. 

 

if i expand any other column i get 400 rows. why is this happening? its multiplication to the number of rows. please help how can i fix this? 

 

 

PBIDesktop_2017-11-27_19-50-25.png

1 ACCEPTED SOLUTION
MarcelBeug
Community Champion
Community Champion

It's quite logical that each expansion of a column with nested tables will create additional rows, so the other columns will be duplicated the same number of times; also the other columns with nested tables.

 

There is a way to combine the nested tables, as illustrated in the query below.

 

However, I wonder how your query looks like so far.

It looks rather strange to me that you arrived in the situation with the nested tables.

 

Maybe you can share your query with some fake data?

 

Query CombinedTables:

 

let
    Source = 
        #table(
            type table[LeadId = Value.Type(Table1), First Name = Value.Type(Table2), Created Time = Value.Type(Table3)],
            {{Table1,Table2,Table3}}),

    #"Added Custom" =
        Table.AddColumn(
            Source, 
            "CombinedTables", 
            each Table.FromColumns(
                Table.ToColumns(
                    [LeadId])&
                Table.ToColumns(
                    [First Name])&
                Table.ToColumns([Created Time]), 
                Value.Type([LeadId]&[First Name]&[Created Time])), 
            Value.Type(Source[LeadId]{0}&Source[First Name]{0}&Source[Created Time]{0})),

    #"Removed Other Columns" = 
        Table.SelectColumns(
            #"Added Custom",
            {"CombinedTables"}),

    #"Expanded CombinedTables" = 
        Table.ExpandTableColumn(
            #"Removed Other Columns", 
            "CombinedTables",
            {"LeadID", "First Name", "Created Time"},
            {"LeadID", "First Name", "Created Time"})
in
    #"Expanded CombinedTables"

 

The 3 tables and my queries:

 

Combine tables.png

Specializing in Power Query Formula Language (M)

View solution in original post

2 REPLIES 2
v-ljerr-msft
Microsoft Employee
Microsoft Employee

Hi @eyaskelani,

 

Have you tried the solution provided by @MarcelBeug above? Does it work in your scenario? If it works, could you accept it as solution to close this thread?

 

If you still have any question on this issue, feel free to post here. Smiley Happy

 

Regards

MarcelBeug
Community Champion
Community Champion

It's quite logical that each expansion of a column with nested tables will create additional rows, so the other columns will be duplicated the same number of times; also the other columns with nested tables.

 

There is a way to combine the nested tables, as illustrated in the query below.

 

However, I wonder how your query looks like so far.

It looks rather strange to me that you arrived in the situation with the nested tables.

 

Maybe you can share your query with some fake data?

 

Query CombinedTables:

 

let
    Source = 
        #table(
            type table[LeadId = Value.Type(Table1), First Name = Value.Type(Table2), Created Time = Value.Type(Table3)],
            {{Table1,Table2,Table3}}),

    #"Added Custom" =
        Table.AddColumn(
            Source, 
            "CombinedTables", 
            each Table.FromColumns(
                Table.ToColumns(
                    [LeadId])&
                Table.ToColumns(
                    [First Name])&
                Table.ToColumns([Created Time]), 
                Value.Type([LeadId]&[First Name]&[Created Time])), 
            Value.Type(Source[LeadId]{0}&Source[First Name]{0}&Source[Created Time]{0})),

    #"Removed Other Columns" = 
        Table.SelectColumns(
            #"Added Custom",
            {"CombinedTables"}),

    #"Expanded CombinedTables" = 
        Table.ExpandTableColumn(
            #"Removed Other Columns", 
            "CombinedTables",
            {"LeadID", "First Name", "Created Time"},
            {"LeadID", "First Name", "Created Time"})
in
    #"Expanded CombinedTables"

 

The 3 tables and my queries:

 

Combine tables.png

Specializing in Power Query Formula Language (M)

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