C# LINQ或for循环如何从数据库中获取数据源？

using System;
using System.Linq;
using System.Data.Linq;

public class MyDataContext : DataContext
{
    public Table<MyTable> MyTables;
}

public class MyTable
{
    public int Id { get; set; }
    public string Name { get; set; }
}

public class Program
{
    public static void Main()
    {
        // 创建数据上下文实例
        using (MyDataContext context = new MyDataContext())
        {
            // 编写LINQ查询
            var query = from t in context.MyTables
                        where t.Id > 10
                        select t;

            // 执行查询并处理结果
            foreach (var item in query)
            {
                Console.WriteLine($"Id: {item.Id}, Name: {item.Name}");
            }
        }
    }
}

using System;
using System.Data;
using System.Data.SqlClient;

public class Program
{
    public static void Main()
    {
        string connectionString = "your_connection_string_here";
        string sqlQuery = "SELECT Id, Name FROM MyTable WHERE Id > @Id";

        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            SqlCommand command = new SqlCommand(sqlQuery, connection);
            command.Parameters.AddWithValue("@Id", 10);

            try
            {
                connection.Open();
                SqlDataReader reader = command.ExecuteReader();

                while (reader.Read())
                {
                    int id = reader.GetInt32(reader.GetOrdinal("Id"));
                    string name = reader.GetString(reader.GetOrdinal("Name"));
                    Console.WriteLine($"Id: {id}, Name: {name}");
                }

                reader.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"An error occurred: {ex.Message}");
            }
        }
    }
}