C# : from in where let select, 資料庫語法

public class Example_of_From_In_Let_Select
{
    public static void Main(string[] args)
    {
        string names = "Mr.Adam,Mrs.Eva,Mr.Henry,MS.May";
        var array = names.Split(',');
       
        var result = (
                from name in array
                where (name.Substring(0, name.IndexOf('.')) == "Mr" )
                let new_name = name + "<Male>"
                select new_name
            );
       
        foreach(string x in result)
            Console.WriteLine(x);
    }
}

/////// Output ///////

Mr.Adam<Male>

Mr.Henry<Male>