拿entity framework与原始的ADO.NET 2.0对比看看。
我一直很犹豫该不该在项目使用entity framework,因为用ADO.NET 2.0,搭配codesmith开发效率也是挺高的,并且ADO.NET对团队的素质要求相对没entity framework那么高,在公司资源有限,无法招揽些开发能力较高的程序员的情况下,是否该用entity framework呢?
这篇文章没有要得出什么结论,纯粹是我学习entity framework的过程中的一些试验笔记。
建了个表,对应的实体:
public class User
{
[Key]
public int UserId { get; set; }
public string Name { get; set; }
public string Address { get; set; }
}
1.运行:
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
User u = new User { Name = "test3", Address = "some address" };
Console.WriteLine(DateTime.Now.ToLongTimeString());
//mc.Configuration.AutoDetectChangesEnabled = false;
mc.Users.Add(u);
//mc.Configuration.AutoDetectChangesEnabled = true;
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.SaveChanges();
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}
看起来,Add方法比较耗时;
2.把AutoDetectChangesEnabled设置为false运行:
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
User u = new User { Name = "test3", Address = "some address" };
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.Configuration.AutoDetectChangesEnabled = false;
mc.Users.Add(u);
mc.Configuration.AutoDetectChangesEnabled = true;
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.SaveChanges();
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}
看起来效果差不多。
3.如果insert 10000行数据:
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
try
{
Console.WriteLine(DateTime.Now.ToLongTimeString());
//mc.Configuration.AutoDetectChangesEnabled = false;
for (int i = 0; i < 10000; i++)
{
User u = new User { Name = "test" + i.ToString(), Address = "some address" };
mc.Users.Add(u);
}
}
finally
{
//mc.Configuration.AutoDetectChangesEnabled = true;
}
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.SaveChanges();
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}
看起来,Add方法特别耗时,注意:如果这里使用mc.Users.AddRange(XXX)去insert10000行数据,速度就会比较快;
4.把AutoDetectChangesEnabled设置为false运行insert 10000行数据:
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
try
{
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.Configuration.AutoDetectChangesEnabled = false;
for (int i = 0; i < 10000; i++)
{
User u = new User { Name = "test" + i.ToString(), Address = "some address" };
mc.Users.Add(u);
}
}
finally
{
mc.Configuration.AutoDetectChangesEnabled = true;
}
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.SaveChanges();
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}
速度快很多。
5.普通ADO.NET insert 10000行数据:
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
string sql = "insert into Users(Name,Address) values (@Name,@Address) ";
Console.WriteLine(DateTime.Now.ToLongTimeString());
for (int i = 0; i < 10000; i++)
{
System.Data.SqlClient.SqlParameter[] paras = {
new System.Data.SqlClient.SqlParameter("@Name ", System.Data.SqlDbType.NVarChar),
new System.Data.SqlClient.SqlParameter("@Address ", System.Data.SqlDbType.NVarChar)
};
paras[0].Value = "test" + i.ToString();
paras[0].Value = "some address";
SqlHelper.sqlToExecute(sql, paras);
}
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}
速度确实是最快的。
以上是insert的,现在试试update 10000 行数据:
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
try
{
var lst = mc.Users.ToList();//数据库有10000行数据
Console.WriteLine(DateTime.Now.ToLongTimeString());
//mc.Configuration.AutoDetectChangesEnabled = false;
foreach (var a in lst)
{
a.Address = a.Address + "1000";
}
}
finally
{
//mc.Configuration.AutoDetectChangesEnabled = true;
}
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.SaveChanges();
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}
看起来,update的速度是很让人满意的。
那么delete呢?
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
try
{
var lst = mc.Users.ToList();
Console.WriteLine(DateTime.Now.ToLongTimeString());
//mc.Configuration.AutoDetectChangesEnabled = false;
foreach (var a in lst)
{
mc.Users.Remove(a);
}
//如果直接用mc.Users.RemoveRange(lst);,也会快的
}
finally
{
//mc.Configuration.AutoDetectChangesEnabled = true;
}
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.SaveChanges();
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}
看起来特别慢;
然而如果加上mc.Configuration.AutoDetectChangesEnabled = false,速度就上来了:
static void Main(string[] args)
{
using(MyContext mc = new MyContext())
{
try
{
var lst = mc.Users.ToList();
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.Configuration.AutoDetectChangesEnabled = false;
foreach (var a in lst)
{
mc.Users.Remove(a);
}
}
finally
{
mc.Configuration.AutoDetectChangesEnabled = true;
}
Console.WriteLine(DateTime.Now.ToLongTimeString());
mc.SaveChanges();
Console.WriteLine(DateTime.Now.ToLongTimeString());
}
}