// Dapper Plus

// Doc: https://dapper-tutorial.net/query

​

// @nuget: Dapper -Version 1.60.6

​

using Dapper;

using System;

using System.Data;

using System.Data.SqlClient;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public class Order

    {

        public int OrderID { get; set; }

        public int CustomerID { get; set; }

        public DateTime OrderDate  { get; set; }

        public int ShipperID  { get; set; }

    }

​

    public static void Main()

    {

        string sql = @"

            SELECT TOP 10

                EmployeeID,

                OrderID,

                CustomerID,

                OrderDate,

                ShipperID

            FROM Orders 

            ORDER BY OrderID;

        ";

​

        using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools()))

        {           

                var dict = connection.Query<int, Order, ValueTuple<int, Order>>(sql,

                    (s, i) => ValueTuple.Create(s, i), splitOn: "OrderID")

                    .GroupBy(t => t.Item1, t => t.Item2, (k, v) => new {Key = k, List = v})

                    .ToDictionary(kv => kv.Key, kv => kv.List);

            foreach (var kv in dict) {

                Console.WriteLine("key: " + kv.Key);

                FiddleHelper.Dump(kv.Value);

                Console.WriteLine();

            }

        }

    }

}