subtracting time from date/time power query

Hi Anonymous ,

If you want to achieve your desired output with Power Query, you could refer to my code below.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwtNQ11DVVMDCyMjS1MjBQ0lEyMATSIGasDlyBIYoCA5iCWAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [#"Date/Time" = _t, Time = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date/Time", type datetime}, {"Time", type time}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each DateTime.Time([#"Date/Time"])-[Time]),
    #"Split Column by Position" = Table.SplitColumn(Table.TransformColumnTypes(#"Added Custom", {{"Custom", type text}}, "en-US"), "Custom", Splitter.SplitTextByPositions({0, 1}, false), {"Custom.1", "Custom.2"}),
    #"Removed Columns" = Table.RemoveColumns(#"Split Column by Position",{"Custom.1"}),
    #"Split Column by Delimiter" = Table.SplitColumn(Table.TransformColumnTypes(#"Removed Columns", {{"Date/Time", type text}}, "en-US"), "Date/Time", Splitter.SplitTextByDelimiter("#(tab)", QuoteStyle.Csv), {"Date/Time.1", "Date/Time.2"}),
    #"Duplicated Column" = Table.DuplicateColumn(#"Split Column by Delimiter", "Date/Time.1", "Date/Time.1 - Copy"),
    #"Split Column by Delimiter1" = Table.SplitColumn(#"Duplicated Column", "Date/Time.1 - Copy", Splitter.SplitTextByDelimiter(" ", QuoteStyle.Csv), {"Date/Time.1 - Copy.1", "Date/Time.1 - Copy.2", "Date/Time.1 - Copy.3"}),
    #"Changed Type1" = Table.TransformColumnTypes(#"Split Column by Delimiter1",{{"Date/Time.1", type datetime}, {"Date/Time.2", type text}, {"Custom.2", type time}, {"Date/Time.1 - Copy.1", type date}, {"Date/Time.1 - Copy.2", type time}, {"Date/Time.1 - Copy.3", type text}}),
    #"Removed Columns1" = Table.RemoveColumns(#"Changed Type1",{"Date/Time.2", "Date/Time.1 - Copy.2", "Date/Time.1 - Copy.3"}),
    #"Changed Type2" = Table.TransformColumnTypes(#"Removed Columns1",{{"Date/Time.1 - Copy.1", type text}, {"Custom.2", type text}}),
    #"Added Custom1" = Table.AddColumn(#"Changed Type2", "Custom", each [#"Date/Time.1 - Copy.1"]&" "&[Custom.2]),
    #"Changed Type3" = Table.TransformColumnTypes(#"Added Custom1",{{"Custom", type datetime}})
in
    #"Changed Type3"

Here is the output.

In addition, ImkeF may have other simpler solution for your requirement.

Best  Regards,

Cherry

The key lies in not transforming the Time-column to Time, but to duration instead in the first "Changed Type"-step.

Then you can simply subtract it like so:

let 
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwtNQ11DVVMDCyMjS1MjBQ0lEyMATSIGasDlyBIYoCY5iCWAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [#"Date/Time" = _t, Time = _t]), 
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date/Time", type datetime}, {"Time", type duration}}), 
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Custom", each [#"Date/Time"]-[Time])
in
    #"Added Custom"