Date Transformation

Hi mburkett ,

Suppose we have:

Please follow these steps:

1. Duplicated [Date] Column:

2. Change [Date - Copy]'s Type from [Date] to [Date/Time]

3. Add a custom column:

if [#"Date - Copy"] > DateTime.LocalNow()
then Date.AddYears([Date],-1)
else [Date]

4. Remove and rename columns.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("Vc65DQAgDAPAXaiRwAnvLCj7r4EokOzyujsnoaBYNU+RH4zhjMbojMGYjMXYDFSRHCAJyALSwH/EBQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type date}}),
    #"Duplicated Column" = Table.DuplicateColumn(#"Changed Type", "Date", "Date - Copy"),
    #"Changed Type1" = Table.TransformColumnTypes(#"Duplicated Column",{{"Date - Copy", type datetime}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type1", "Custom", each if [#"Date - Copy"] > DateTime.LocalNow()
then Date.AddYears([Date],-1)
else [Date]),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"Date", "Date - Copy"}),
    #"Renamed Columns" = Table.RenameColumns(#"Removed Columns",{{"Custom", "Date"}})
in
    #"Renamed Columns"

Best Regards,
Gao
Community Support Team

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