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Question

我需要通过 ADO.Net 优化我的数据访问。对于项目的要求，我不能使用 Linq 或 Entity...

所以我发起了 15 个独立 ADO.NET 查询。我遵循标准，打开连接，启动查询，使用 DataReader 获取数据，将它们存储在类中，最后我关闭连接...

但我觉得这个项目还不够快。那么，伙计们，你们能教我一些提高速度的技巧吗？

我的数据库是 SQL 服务器，我会尽我所能按实体启动查询。

已编辑：

private void Connect(string comando) {
    try { 
        string cadena = "connection_data";
        Cn = new SqlConnection(cadena);
        Cn.Open();
        SqlCommand Com = new SqlCommand(comando, Cn);
        Datos = Com.ExecuteReader();
    }
    catch (Exception e)
    {
        // 
    }
}

    private void Close()
    {
        try 
        { 
            Cn.Close();
            Datos.Close();
        }
        catch (Exception e)
        {
            // 
        }
    }

    public List<class1> getClass1(double id)
    {
        Connect("SELECT TOP (5) CASE WHEN [table1].[attribute1] IN (7, 12, 13, 14, 15, 16, 17, 18, 19, 28, 29) THEN 'random_name' " +
            "WHEN [table1].[attribute3] = NULL AND [table1].[attribute2] = NULL THEN 'random_name2' WHEN [table1].[attribute3] = NULL THEN [table1].[attribute3] ELSE " 
// bla bla bla bla and so on and I have 15 massive queries like this one;

        List<class1> res = new List<class1>();

        if (Datos.HasRows == true)
        {
            while (Datos.Read())
            {
                class1obj = new class1();
                obj.at1= class1.cont + 1;
                obj.at2= class1.cont + 1;
                class1.cont++;
                obj.at3= "random_value";
                obj.at4= Datos.GetValue(0);
                obj.at5= Datos.GetValue(1);
                res.Add(obj);
            }
            Close();
        }
        return res;
    }

Answer 1

如果你确实有为每个 class 创建的功能，那么你可以做的是这样的：

不是函数getClass1而是接口：

public interface IBuildClass<TClass>
{
    Task<IEnumerable<TClass>> BuildAsync(double id);
}

为接口添加一个基础 class，该接口将请求作为数据库连接对象的依赖项

public abstract class BuildClassBase<TClass> : IBuildClass<TClass>
{
    public BuildClassBase(SqlConnection connection)
    {
        Connection = connection;
    }

    public async Task<IEnumerable<TClass>> BuildAsync(double id)
    {
        //Execute query and pass results to InnerBuid
        return InnerBuildAsync(/*Pass DataTable*/);
    }

    public abstract async Task<IEnumerable<TClass>> InnerBuildAsync(DataTable data);

    //Ctor of each derived class will set the value
    public string Query { get; protected set; }
    public SqlConnection Connection {get; set; }
}

然后是与您要创建的每个 class 相匹配的特定实现。您还可以为他们添加一个工厂：

public interface IBuildClassFactory
{
    IBuildClass<TClass> GetBuilder<TClass>();
}

然后在您当前执行所有 15 个方法的代码中，您可以为每个 class 创建一个 Task，然后是 await buildClassFactory.GetBuilder<ClassA>().BuildAsync(id)。类似于：

double id = 1;
Task createClassA = buildClassFactory.GetBuilder<ClassA>().BuildAsync(id);
Task createClassB = buildClassFactory.GetBuilder<ClassB>().BuildAsync(id);
Task createClassC = buildClassFactory.GetBuilder<ClassC>().BuildAsync(id);
....

Task.WaitAll(createClassA, createClassB, createClassC....);

//And then get result from tasks

运行并行查询

Running queries in Parallel

c#

asp.net

asp.net-mvc

ado.net

sqldatareader

运行 并行查询

Running queries in Parallel

c#

asp.net

asp.net-mvc

ado.net

sqldatareader

运行并行查询