Forum Discussion

smpa01's avatar
smpa01
Community Champion
3 years ago
Solved

Unpivot Others with null

The following currently eliminates all nulls

 

= Table.UnpivotOtherColumns(
    Table.FromRecords({
        [key = "key1", attribute1 = 1, attribute2 = null, attribute3 = 3],
        [key = "key2", attribute1 = 4, attribute2 = 5, attribute3 = 6]
    }),
    {"key"},
    "column1",
    "column2"
)

 

 I can run a replace prior to this method to replace null to 0.

But I am currently working with a large dataset retrieved through API call and I am not exactly sure what are the other values (other than null) Table.UnpivotOtherColumns is capable of eliminating. I don't want to miss out on any value whatsoever as a result of the method above.
Is there any way to handle this within the UnPivotOtherColumns call itself to instruct PQ to return the value of attributes as is without running multiple replace (per known value UnPivotOtherColumns is capable of eliminating) prior to this call?

ImkeF AlexisOlson 

The following also does not help

Table.UnpivotOtherColumns(Table.TransformColumnTypes(Table.FromRecords({
        [key = "key1", attribute1 = 1, attribute2 = null, attribute3 = 3],
        [key = "key2", attribute1 = 4, attribute2 = 5, attribute3 = 6]
    }),{{"attribute1", type text}, {"attribute2", type text}, {"attribute3", type text}}), {"key"}, "Attribute", "Value")

 

  • Hi smpa01 ,
    yes, no need for an (un)pivot operation here. The following method will keep all values by default:

    let
        Custom1 = Table.FromRecords({
            [key = "key1", attribute1 = 1, attribute2 = null, attribute3 = 3],
            [key = "key2", attribute1 = 4, attribute2 = 5, attribute3 = 6]
        }),
        #"Added Custom" = Table.AddColumn(Custom1, "OtherValues", each Record.ToTable(Record.RemoveFields(_, {"key"}))),
        #"Removed Other Columns" = Table.SelectColumns(#"Added Custom",{"key", "OtherValues"}),
        #"Expanded OtherValues" = Table.ExpandListColumn(#"Removed Other Columns", "OtherValues"),
        #"Expanded OtherValues1" = Table.ExpandRecordColumn(#"Expanded OtherValues", "OtherValues", {"Name", "Value"}, {"Name", "Value"})
    in
        #"Expanded OtherValues1"

     

3 Replies

  • ImkeF's avatar
    ImkeF
    Community Champion

    Hi smpa01 ,
    yes, no need for an (un)pivot operation here. The following method will keep all values by default:

    let
        Custom1 = Table.FromRecords({
            [key = "key1", attribute1 = 1, attribute2 = null, attribute3 = 3],
            [key = "key2", attribute1 = 4, attribute2 = 5, attribute3 = 6]
        }),
        #"Added Custom" = Table.AddColumn(Custom1, "OtherValues", each Record.ToTable(Record.RemoveFields(_, {"key"}))),
        #"Removed Other Columns" = Table.SelectColumns(#"Added Custom",{"key", "OtherValues"}),
        #"Expanded OtherValues" = Table.ExpandListColumn(#"Removed Other Columns", "OtherValues"),
        #"Expanded OtherValues1" = Table.ExpandRecordColumn(#"Expanded OtherValues", "OtherValues", {"Name", "Value"}, {"Name", "Value"})
    in
        #"Expanded OtherValues1"

     

    • smpa01's avatar
      smpa01
      Community Champion

      ImkeF  this is simply awesome and thanks for this.

      One follow-up Q - is there any performance implication with the above for a large dataset?

  • ImkeF's avatar
    ImkeF
    Community Champion

    Hi smpa01 ,
    I haven't tested it, but my guess is that this should perform very well, as the operation is completely on row-level.