Timestamp when true

Hi philerob2014 ,

Ok, I think I now understand a bit better what you are after. For your scenario I suggest you use Power Query:

Before:

After:

I applied the following logic:

if [Column] = true and [timestamp] <> null then [timestamp] else if [Column] = true and [timestamp] = null then DateTime.LocalNow() else if [Column] = false and [timestamp] <> null then null else null

Here the code for the advanced editor:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WKikqTVXSUTIyMDLSNTTSNTBTMDSyMjAAIqVYnWiltMScYnR5QyzyYA7ULFR2LAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column = _t, timestamp = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Column", type logical}, {"timestamp", type datetime}}),
    #"Replace Values" = Table.ReplaceValue(#"Changed Type",each [timestamp],each if [Column] = true and [timestamp] <> null then [timestamp] else if [Column] = true and [timestamp] = null then DateTime.LocalNow() else if [Column] = false and [timestamp] <> null then null else null, Replacer.ReplaceValue,{"timestamp"})

in
    #"Replace Values"

In case you haven't worked with Power Query before, I'd suggest to start with a blank query and look into the steps above. I am sure you will be able to figure it out how to align your code 🙂 Otherwise, you could also just create a new column with the if logic above. If you are happy with it and you want to overwrite your timestamp column, I'd suggest to check out this blog post, where you can learn how to substitute values (instead of creating a new column)