SQL Server CE 4.0性能比较

Question

SQL Server CE 4（SQL Server Compact Edition 4.0）已不是新闻（如果是，您可以read this article）

但是看到SQL Server CE 4与其他数据库的性能比较非常有趣。

特别是：

• SQLite
• SQL Server（1）
• SQL Server Express *
• 也许Firebird

（1）适用于功能相当的应用程序。

不幸的是，目前google提供的主题没有那么多链接。实际上我找不到任何（适当的SQL CE版本）。

如果有人能够找到或分享这些信息，我们可以在这里收集它以供将来人道使用。

Answer 1

Answer 2

以下是关于CodeProject网页基准测试的新近出版的文章：

Benchmarking the performance of embedded DB for .Net: SQL CE 4.0 vs SQLite

（该文章现在处于暂挂状态，您需要登录CodeProject才能访问其内容）

P.S。：我错误地将我以前的答案标记为社区维基条目，并且不会因此获得任何声誉。这鼓励我为Code Project撰写关于此主题的文章，其中包含一些优化的代码，有关嵌入式dbs的更多其他信息以及结果的统计分析。所以，如果您喜欢这篇文章和我的第二个答案，请将此答案投票。

Answer 3

因为我在Alaudo的测试，测试结果以及最终的结论方面遇到了真正的困难，所以我继续使用他的程序玩了一下并提出了修改版本。

它测试以下每个10次并输出平均时间：

• 没有交易的sqlite，使用默认的jounal_mode
• 带有事务的sqlite，使用默认的journal_mode
• 没有事务的sqlite，使用WAL jounal_mode
• 带有事务的sqlite，使用WAL journal_mode
• 没有交易的sqlce
• 带有交易的sqlce

这是程序（实际上是一个类）：

using System;
using System.Collections.Generic;
using System.Data.Common;
using System.Data.SqlServerCe;
using System.Data.SQLite;
using System.Diagnostics;
using System.IO;
using System.Linq;

class SqliteAndSqlceSpeedTesting
{
    class Results
    {
        public string test_details;
        public long create_table_time, insert_time, update_time, select_time, delete_time, drop_table_time;
    }

    enum DbType { Sqlite, Sqlce };

    const int NUMBER_OF_TESTS = 200;
    const string create_table_sqlite = "CREATE TABLE Test (id integer not null primary key, textdata nvarchar(500));";
    const string create_table_sqlce = "CREATE TABLE Test (id integer not null identity primary key, textdata nvarchar(500));";
    const string drop_table = "DROP TABLE Test";
    const string insert_data = "INSERT INTO Test (textdata) VALUES ('{0}');";
    const string read_data = "SELECT textdata FROM Test WHERE id = {0}";
    const string update_data = "UPDATE Test SET textdata = '{1}' WHERE id = {0}";
    const string delete_data = "DELETE FROM Test WHERE id = {0}";

    public static void RunTests()
    {
        List<Results> results_list = new List<Results>();

        for (int i = 0; i < 10; i++) {
            results_list.Add(RunTest(DbType.Sqlite, false, false));
            results_list.Add(RunTest(DbType.Sqlite, false, true));
            results_list.Add(RunTest(DbType.Sqlite, true, false));
            results_list.Add(RunTest(DbType.Sqlite, true, true));
            results_list.Add(RunTest(DbType.Sqlce, false));
            results_list.Add(RunTest(DbType.Sqlce, true));                
        }

        foreach (var test_detail in results_list.GroupBy(r => r.test_details)) {
            Console.WriteLine(test_detail.Key);
            Console.WriteLine("Creating table: {0} ms", test_detail.Average(r => r.create_table_time));
            Console.WriteLine("Inserting data: {0} ms", test_detail.Average(r => r.insert_time));
            Console.WriteLine("Updating data: {0} ms", test_detail.Average(r => r.update_time));
            Console.WriteLine("Selecting data: {0} ms", test_detail.Average(r => r.select_time));
            Console.WriteLine("Deleting data: {0} ms", test_detail.Average(r => r.delete_time));
            Console.WriteLine("Dropping table: {0} ms", test_detail.Average(r => r.drop_table_time));
            Console.WriteLine();
        }
    }

    static Results RunTest(DbType db_type, bool use_trx, bool use_wal = false)
    {
        DbConnection conn = null;
        if (db_type == DbType.Sqlite)
            conn = GetConnectionSqlite(use_wal);
        else
            conn = GetConnectionSqlce();

        Results results = new Results();
        results.test_details = string.Format("Testing: {0}, transactions: {1}, WAL: {2}", db_type, use_trx, use_wal);
        results.create_table_time = CreateTable(conn, db_type);
        results.insert_time = InsertTime(conn, use_trx);
        results.update_time = UpdateTime(conn, use_trx);
        results.select_time = SelectTime(conn, use_trx);
        results.delete_time = DeleteTime(conn, use_trx);
        results.drop_table_time = DropTableTime(conn);
        conn.Close();
        return results;
    }

    static DbConnection GetConnectionSqlite(bool use_wal)
    {
        SQLiteConnection conn = new SQLiteConnection("Data Source=sqlite.db");
        if (!File.Exists(conn.Database))
            SQLiteConnection.CreateFile("sqlite.db");
        conn.Open();
        if (use_wal) {
            var command = conn.CreateCommand();
            command.CommandText = "PRAGMA journal_mode=WAL";
            command.ExecuteNonQuery();
        }
        return conn;
    }

    static DbConnection GetConnectionSqlce()
    {
        SqlCeConnection conn = new SqlCeConnection("Data Source=sqlce.sdf");
        if (!File.Exists(conn.Database))
            using (var sqlCeEngine = new SqlCeEngine("Data Source=sqlce.sdf"))
                sqlCeEngine.CreateDatabase();
        conn.Open();
        return conn;
    }

    static long CreateTable(DbConnection con, DbType db_type)
    {
        Stopwatch sw = Stopwatch.StartNew();
        var sqlcmd = con.CreateCommand();
        if (db_type == DbType.Sqlite)
            sqlcmd.CommandText = create_table_sqlite;
        else
            sqlcmd.CommandText = create_table_sqlce;
        sqlcmd.ExecuteNonQuery();
        return sw.ElapsedMilliseconds;
    }

    static long DropTableTime(DbConnection con)
    {
        Stopwatch sw = Stopwatch.StartNew();
        var sqlcmd = con.CreateCommand();
        sqlcmd.CommandText = drop_table;
        sqlcmd.ExecuteNonQuery();
        return sw.ElapsedMilliseconds;
    }

    static long InsertTime(DbConnection con, bool use_trx)
    {
        Stopwatch sw = Stopwatch.StartNew();
        var sqlcmd = con.CreateCommand();
        DbTransaction trx = null;
        if (use_trx) {
            trx = con.BeginTransaction();
            sqlcmd.Transaction = trx;
        }
        for (int i = 0; i < NUMBER_OF_TESTS; i++) {
            sqlcmd.CommandText = string.Format(insert_data, Guid.NewGuid().ToString());
            sqlcmd.ExecuteNonQuery();
        }
        if (trx != null)
            trx.Commit();
        return sw.ElapsedMilliseconds;
    }

    static long SelectTime(DbConnection con, bool use_trx)
    {
        Stopwatch sw = Stopwatch.StartNew();
        var sqlcmd = con.CreateCommand();
        DbTransaction trx = null;
        if (use_trx) {
            trx = con.BeginTransaction();
            sqlcmd.Transaction = trx;
        }
        Random rnd = new Random(DateTime.Now.Millisecond);
        for (var max = NUMBER_OF_TESTS; max-- > 0; ) {
            sqlcmd.CommandText = string.Format(read_data, rnd.Next(1, NUMBER_OF_TESTS - 1));
            sqlcmd.ExecuteNonQuery();
        }
        if (trx != null)
            trx.Commit();
        return sw.ElapsedMilliseconds;
    }

    static long UpdateTime(DbConnection con, bool use_trx)
    {
        Stopwatch sw = Stopwatch.StartNew();
        var sqlcmd = con.CreateCommand();
        DbTransaction trx = null;
        if (use_trx) {
            trx = con.BeginTransaction();
            sqlcmd.Transaction = trx;
        }
        Random rnd = new Random(DateTime.Now.Millisecond);
        for (var max = NUMBER_OF_TESTS; max-- > 0; ) {
            sqlcmd.CommandText = string.Format(update_data, rnd.Next(1, NUMBER_OF_TESTS - 1), Guid.NewGuid().ToString());
            sqlcmd.ExecuteNonQuery();
        }
        if (trx != null)
            trx.Commit();
        return sw.ElapsedMilliseconds;
    }

    static long DeleteTime(DbConnection con, bool use_trx)
    {
        Stopwatch sw = Stopwatch.StartNew();
        Random rnd = new Random(DateTime.Now.Millisecond);
        var order = Enumerable.Range(1, NUMBER_OF_TESTS).ToArray<int>();
        Action<int[], int, int> swap = (arr, a, b) => { int c = arr[a]; arr[a] = arr[b]; arr[b] = c; };
        var sqlcmd = con.CreateCommand();
        DbTransaction trx = null;
        if (use_trx) {
            trx = con.BeginTransaction();
            sqlcmd.Transaction = trx;
        }
        // shuffling the array
        for (var max = NUMBER_OF_TESTS; max-- > 0; ) swap(order, rnd.Next(0, NUMBER_OF_TESTS - 1), rnd.Next(0, NUMBER_OF_TESTS - 1));

        foreach (int index in order) {
            sqlcmd.CommandText = string.Format(delete_data, index);
            sqlcmd.ExecuteNonQuery();
        }
        if (trx != null)
            trx.Commit();
        return sw.ElapsedMilliseconds;
    }
}

以下是我得到的数字：

Testing: Sqlite, transactions: False, WAL: False
Creating table: 24.4 ms
Inserting data: 3084.7 ms
Updating data: 3147.8 ms
Selecting data: 30 ms
Deleting data: 3182.6 ms
Dropping table: 14.5 ms

Testing: Sqlite, transactions: False, WAL: True
Creating table: 2.3 ms
Inserting data: 14 ms
Updating data: 12.2 ms
Selecting data: 6.8 ms
Deleting data: 11.7 ms
Dropping table: 0 ms

Testing: Sqlite, transactions: True, WAL: False
Creating table: 13.5 ms
Inserting data: 20.3 ms
Updating data: 24.5 ms
Selecting data: 7.8 ms
Deleting data: 22.3 ms
Dropping table: 16.7 ms

Testing: Sqlite, transactions: True, WAL: True
Creating table: 3.2 ms
Inserting data: 5.8 ms
Updating data: 4.9 ms
Selecting data: 4.4 ms
Deleting data: 3.8 ms
Dropping table: 0 ms

Testing: Sqlce, transactions: False, WAL: False
Creating table: 2.8 ms
Inserting data: 24.4 ms
Updating data: 42.8 ms
Selecting data: 30.4 ms
Deleting data: 38.3 ms
Dropping table: 3.3 ms

Testing: Sqlce, transactions: True, WAL: False
Creating table: 2.1 ms
Inserting data: 24.6 ms
Updating data: 44.2 ms
Selecting data: 32 ms
Deleting data: 37.8 ms
Dropping table: 3.2 ms

使用sqlite进行200次插入或更新的时间~3秒可能看起来仍然有点高，但至少它比23秒更合理。相反，人们可能会担心SqlCe如何花费太少的时间来完成相同的200次插入或更新，尤其是因为在单个事务中使用每个SQL查询或在一个事务中一起使用时，似乎没有真正的速度差异。我不太了解SqlCe来解释这一点，但它让我担心。是否意味着当.Commit（）返回时，您不确定更改是否实际写入磁盘？

Answer 4

我最近使用SQL CE 4和NHibernate开展了一个项目，我发现性能非常好。使用SQL CE 4，我们能够在一秒钟内插入8000条记录。通过网络上的Oracle，我们每秒只能插入100条记录，甚至使用批量大小和seqhilo方法。

我没有测试它，但是查看一些针对.NET的NoSQL产品的性能报告，SQL CE 4似乎是独立应用程序的最佳解决方案之一。

只是避免使用Identity列，我们注意到如果不使用它们，性能会提高40倍。当Identity列用作PK时，相同的8000条记录需要40秒才能插入。