let
    Source = #table(
        type table [Category = text, Sales = number],
        {
            {"A", 100},
            {"A", 200},
            {"B", 300}
        }
    ),
    Grouped = Table.Group(
        Source,
        {"Category"},
        {{"TotalSales", each List.Sum([Sales]), type number}}     )
in
    Grouped

let
    Source = #table(
        type table [Category = text, Sales = number],
        {
            {"A", 100},
            {"A", 200},
            {"B", 300}
        }
    ),
    Grouped = Table.Group(
        Source,
        {"Category"},
        {{"Count", each Table.RowCount(_), Int64.Type}}     )
in
    Grouped