Entity Framwork Vs ADO .Net Vs Dapper .Net 效率比较

由我另一个博客拷贝
近年来一直使用EF+.Net MVC来编写系统，由于最近换了一个公司，碰到一个印度同事，他告诉我用Dapper比用EF高效很多，基本可以接近ADO .Net 的效率，因为习惯的问题一直没有对ORM做深入的了解的解析，所以借此机会对此三种方法进行效率测试，以便今后做大型数据处理时可以有更多的选择性。测试用例借鉴了 here。

比较版本

EF 6.2.0， Dapper 1.50.4

数据表结构

    public class Sport
    {
        public Sport()
        {
            Teams = new HashSet();
        }
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Id { get; set; }
        public string Name { get; set; }
        public ICollection Teams { get; set; }
    }

    public class Team
    {
        public Team()
        {
            Players = new HashSet();
        }
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Id { get; set; }
        public string Name { get; set; }

        public DateTime FoundingDate { get; set; }
        [ForeignKey("Sport")]
        public int SportId { get; set; }
        public Sport Sport { get; set; }
        public ICollection Players { get; set; }
    }

    public class Player
    {
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Id { get; set; }
        public string  FirstName { get; set; }
        public string  LastName { get; set; }
        public DateTime DateOfBirth { get; set; }
        [ForeignKey("Team")]
        public int TeamId { get; set; }
        public Team Team { get; set; }
    }

数据

Sports表加入47个不同的运动项目，大家可以网上自行搜索后加入，
Teams随即生产1000个Team，并随机分配到Sport
Players随机生成100万个Player，并随机分配到Team
数据库由EF Code First生成，并且使用比较熟悉的EF加入数据

查询Interface.

    public interface ITestORM
    {
        long GetPlayerByID(int id);
        long GetPlayersForTeam(int teamId);
        long GetPlayersForSport(int sportId);
    }

GetPlayerByID: 根据运动员编号（主键）查找运动员
GetPlayersForTeam: 查找给定Team编号的所有运动员
GetPlayersForSport: 查找给定Sport编号的所有运动员
所以方法都不返回查找的结果，只是返回一个tick值（一千万分之一秒）
每个方法运行10次，并且取得平均值和搜寻的总时长进行比较

Entity Framework 实现代码

    public class EFORM : ITestORM
    {
        private bool _tracking = true;
        public EFORM()
        {

        }
        public EFORM(bool tracking)
        {
            _tracking = tracking;
        }
        public long GetPlayerByID(int id)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (TestORMContext context = new TestORMContext())
            {
                if (!_tracking)
                {
                    var player = context.Players.AsNoTracking().Where(x => x.Id == id).First();
                }
                else
                {
                    var player = context.Players.Where(x => x.Id == id).First();
                }

            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }

        public long GetPlayersForTeam(int teamId)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (TestORMContext context = new TestORMContext())
            {
                if (!_tracking)
                {
                    var players = context.Players.AsNoTracking().Where(x => x.TeamId == teamId).ToList();
                }
                else
                {
                    var players = context.Players.Where(x => x.TeamId == teamId).ToList();
                }
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }

        public long GetPlayersForSport(int sportId)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (TestORMContext context = new TestORMContext())
            {
                if (!_tracking)
                {
                    var players = context.Players.AsNoTracking().Where(player => player.Team.Sport.Id == sportId).ToList();
                }
                else
                {
                    var players = context.Players.Where(player => player.Team.Sport.Id == sportId).ToList();
                }
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }
    }

创建EF查询对象时可以用 new EFROM（）–可tracking和new EFROM（false）–不可tracking进行查询，以便区分打开和关闭tracking时所需的查询时间，因为在上述网站上有网友提出不加tracking时，EF效率也很高效

ADO .Net 实现代码

    public class ADO:ITestORM
    {
        public long GetPlayerByID(int id)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["TestORM"].ToString()))            {
                conn.Open();
                using (SqlDataAdapter adapter = new SqlDataAdapter("SELECT Id, FirstName, LastName, DateOfBirth, TeamId FROM Players WHERE Id = @ID", conn))
                {
                    adapter.SelectCommand.Parameters.Add(new SqlParameter("@ID", id));
                    DataTable table = new DataTable();
                    adapter.Fill(table);
                }
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }

        public long GetPlayersForTeam(int teamId)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["TestORM"].ToString()))
            {
                conn.Open();
                using (SqlDataAdapter adapter = new SqlDataAdapter("SELECT Id, FirstName, LastName, DateOfBirth, TeamId FROM Players WHERE TeamId = @ID", conn))
                {
                    adapter.SelectCommand.Parameters.Add(new SqlParameter("@ID", teamId));
                    DataTable table = new DataTable();
                    adapter.Fill(table);
                }
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }

        public long GetPlayersForSport(int sportId)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["TestORM"].ToString()))
            {
                conn.Open();
                using (SqlDataAdapter adapter = new SqlDataAdapter("SELECT p.Id, p.FirstName, p.LastName, p.DateOfBirth, p.TeamId, t.Id as TeamId, t.Name, t.SportId FROM Players p INNER JOIN Teams t ON p.TeamId = t.Id WHERE t.SportId = @ID", conn))
                {
                    adapter.SelectCommand.Parameters.Add(new SqlParameter("@ID", sportId));
                    DataTable table = new DataTable();
                    adapter.Fill(table);
                }
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }
    }

Dapper .Net 实现代码

    public class DapperORM:ITestORM
    {
        public long GetPlayerByID(int id)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["TestORM"].ToString()))
            {
                conn.Open();
                var player = conn.Query("SELECT Id, FirstName, LastName, DateOfBirth, TeamId FROM Players WHERE Id = @ID", new { ID = id });
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }

        public long GetPlayersForTeam(int teamId)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["TestORM"].ToString()))
            {
                conn.Open();
                var players = conn.Query>("SELECT Id, FirstName, LastName, DateOfBirth, TeamId FROM Players WHERE TeamId = @ID", new { ID = teamId });
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }

        public long GetPlayersForSport(int sportId)
        {
            Stopwatch watch = new Stopwatch();
            watch.Start();
            using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["TestORM"].ToString()))
            {
                conn.Open();
                var players = conn.Query("SELECT p.Id, p.FirstName, p.LastName, p.DateOfBirth, p.TeamId, t.Id as TeamId, t.Name, t.SportId FROM Teams t "
                    + "INNER JOIN Players p ON t.Id = p.TeamId WHERE t.SportId = @ID", (player, team) => { return player; }, splitOn: "TeamId", param: new { ID = sportId });
            }
            watch.Stop();
            return watch.ElapsedMilliseconds;
        }
    }

代码说明

上述代码基本都借鉴于 此处，不是完全拷贝，两者有部分地方有区别

测试说明

每种方法中的每个查询函数分别运行10次，每次查询的id为总记录的1/10，分别记录每个查询的时长，EF查询两次，一次tracking，一次no tracking

测试结果

说明: 运动员的编号没有从1开始，所以有下面奇怪的运动员编号 ：P

EF 有 Tracking

查询 1	Tick	查询 2	Tick	查询 3	Tick
GetPlayerByID(1006820)	1801	GetPlayersForTeam(1)	13	GetPlayersForSport(1)	501
GetPlayerByID(1106820)	1	GetPlayersForTeam(101)	11	GetPlayersForSport(5)	312
GetPlayerByID(1206820)	1	GetPlayersForTeam(201)	11	GetPlayersForSport(9)	284
GetPlayerByID(1306820)	1	GetPlayersForTeam(301)	20	GetPlayersForSport(13)	363
GetPlayerByID(1406820)	1	GetPlayersForTeam(401)	24	GetPlayersForSport(17)	457
GetPlayerByID(1506820)	1	GetPlayersForTeam(501)	11	GetPlayersForSport(21)	281
GetPlayerByID(1606820)	0	GetPlayersForTeam(601)	14	GetPlayersForSport(25)	417
GetPlayerByID(1706820)	1	GetPlayersForTeam(701)	17	GetPlayersForSport(29)	344
GetPlayerByID(1806820)	1	GetPlayersForTeam(801)	38	GetPlayersForSport(33)	266
GetPlayerByID(1906820)	1	GetPlayersForTeam(901)	11	GetPlayersForSport(37)	327
平均	180.9		17		355.2
总时长	5531

EF 无 Tracking

查询 1	Tick	查询 2	Tick	查询 3	Tick
GetPlayerByID(1006820)	1760	GetPlayersForTeam(1)	4	GetTeamsForSport(1)	247
GetPlayerByID(1106820)	1	GetPlayersForTeam(101)	3	GetTeamsForSport(5)	180
GetPlayerByID(1206820)	1	GetPlayersForTeam(201)	3	GetTeamsForSport(9)	171
GetPlayerByID(1306820)	1	GetPlayersForTeam(301)	3	GetTeamsForSport(13)	172
GetPlayerByID(1406820)	1	GetPlayersForTeam(401)	4	GetTeamsForSport(17)	197
GetPlayerByID(1506820)	1	GetPlayersForTeam(501)	3	GetTeamsForSport(21)	171
GetPlayerByID(1606820)	1	GetPlayersForTeam(601)	3	GetTeamsForSport(25)	179
GetPlayerByID(1706820)	1	GetPlayersForTeam(701)	3	GetTeamsForSport(29)	181
GetPlayerByID(1806820)	1	GetPlayersForTeam(801)	3	GetTeamsForSport(33)	172
GetPlayerByID(1906820)	1	GetPlayersForTeam(901)	3	GetTeamsForSport(37)	175
平均	177		3		185
总时长	3646

ADO .Net

查询 1	Tick	查询 2	Tick	查询 3	Tick
GetPlayerByID(1006820)	79	GetPlayersForTeam(1)	4	GetPlayersForSport(1)	1834
GetPlayerByID(1106820)	0	GetPlayersForTeam(101)	3	GetPlayersForSport(5)	184
GetPlayerByID(1206820)	0	GetPlayersForTeam(201)	3	GetPlayersForSport(9)	180
GetPlayerByID(1306820)	0	GetPlayersForTeam(301)	3	GetPlayersForSport(13)	184
GetPlayerByID(1406820)	0	GetPlayersForTeam(401)	3	GetPlayersForSport(17)	207
GetPlayerByID(1506820)	0	GetPlayersForTeam(501)	3	GetPlayersForSport(21)	192
GetPlayerByID(1606820)	0	GetPlayersForTeam(601)	3	GetPlayersForSport(25)	194
GetPlayerByID(1706820)	0	GetPlayersForTeam(701)	3	GetPlayersForSport(29)	182
GetPlayerByID(1806820)	0	GetPlayersForTeam(801)	3	GetPlayersForSport(33)	191
GetPlayerByID(1906820)	0	GetPlayersForTeam(901)	3	GetPlayersForSport(37)	184
平均	7.9		3.1		353.2
总时长	3642

Dapper .Net

查询 1	Tick	查询 2	Tick	查询 3	Tick
GetPlayerByID(1006820)	129	GetPlayersForTeam(1)	4	GetPlayersForSport(1)	214
GetPlayerByID(1106820)	0	GetPlayersForTeam(101)	2	GetPlayersForSport(5)	179
GetPlayerByID(1206820)	0	GetPlayersForTeam(201)	2	GetPlayersForSport(9)	176
GetPlayerByID(1306820)	0	GetPlayersForTeam(301)	2	GetPlayersForSport(13)	185
GetPlayerByID(1406820)	0	GetPlayersForTeam(401)	2	GetPlayersForSport(17)	194
GetPlayerByID(1506820)	0	GetPlayersForTeam(501)	2	GetPlayersForSport(21)	182
GetPlayerByID(1606820)	0	GetPlayersForTeam(601)	2	GetPlayersForSport(25)	189
GetPlayerByID(1706820)	0	GetPlayersForTeam(701)	9	GetPlayersForSport(29)	189
GetPlayerByID(1806820)	0	GetPlayersForTeam(801)	2	GetPlayersForSport(33)	176
GetPlayerByID(1906820)	0	GetPlayersForTeam(901)	2	GetPlayersForSport(37)	181
平均	12.9		2.9		186.5
总时长	2023

比较结果

*	EF W Tracking	EF WO Tracking	ADO.Net	Dapper.Net
GetPlayerByID	180.9	176.9	7.9	12.9
GetPlayersForTeam	17	3.2	3.1	2.9
GetPlayersForSport	355.2	184.5	353.2	186.5
Total Time	5531	3646	3642	2023

感觉Dapper真的非常高效，No Tracking的EF效率也不低和ADO .Net不相上下，不过对于在系统中嵌套SQL语言，个人比较不好接受，而且不优雅，对今后维护工作也有一定麻烦，因此今后采用Dapper机会应该不多，除非一些不需要后期维护而且数据量庞大的系统或许会采用。不过仁者见仁，智者见智，当前Dapper好像非常火，但是不管用哪种方法，达到目的，而且效率不要过份低下都不失为一个好的方法。

Richard 于 2017圣诞前