Fill out empty field with text strings in the previous row

Hi ritar_li ,
According to your description, you can first grouping operation and then fill down, the following is the sample data and code

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("hZBfC4IwFMW/ivgszG1E+WgGUVSIbyESQwUHpjKt6Nt3l382Uwkuu+fhnt89d2FoYtMyr/I5FLzhLAcFdWHxG9pelI/KcA2QxzIroDkII2ITacB2ryNL47hJcnOrSg78gragvEzwul2CwU4kgU4JQfrk6aud0wsTRLHykNn0ZybUUg+UzxoueMzUAeQr2/VkjBofMGGdeM26LN0H0Kl/Mb6NVspCZ9Pr5aD1zPg4oc/uac6GjDtQAS+HfZsFgB7xD4L0jOgD", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"Person ID" = _t, Year = _t, Event = _t, Instance = _t, Name = _t, Departme = _t, Supervisor = _t, #"Completetion Date" = _t, #"Review Date" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Person ID", Int64.Type}, {"Year", type text}, {"Event", type text}, {"Instance", Int64.Type}, {"Name", type text}, {"Departme", type text}, {"Supervisor", type text}, {"Completetion Date", type date}, {"Review Date", type date}}),
    ReplacedBlankWithNull = Table.ReplaceValue(#"Changed Type", "", null, Replacer.ReplaceValue, {"Name", "Departme", "Supervisor"}),
    #"Grouped Rows" = Table.Group(ReplacedBlankWithNull, {"Person ID"}, {{"All", each _, type table [Person ID=nullable number, Year=nullable text, Event=nullable text, Instance=nullable number, Name=nullable text, Departme=nullable text, Supervisor=nullable text, Completetion Date=nullable date, Review Date=nullable date]}}),
    FilledDown = Table.TransformColumns(#"Grouped Rows", {"All", each Table.FillDown(_, {"Name", "Departme", "Supervisor"})}),
    #"Expanded All" = Table.ExpandTableColumn(FilledDown, "All", {"Year", "Event", "Instance", "Name", "Departme", "Supervisor", "Completetion Date", "Review Date"}, {"Year", "Event", "Instance", "Name", "Departme", "Supervisor", "Completetion Date", "Review Date"})
in
    #"Expanded All"

Final output

Best regards,
Albert He

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