表值参数不允许使用数据库名称

Question

当我调用Select函数时，我收到以下错误：

传入的表格数据流（TDS）远程过程调用（RPC）协议流不正确。 表值参数3（“@ SearchTableVar”），第0行，第0列：数据类型0xF3（用户定义的表类型）具有指定的非零长度数据库名称。 表值参数不允许使用数据库名称，只有模式名称和类型名称有效。

C＃代码

//DTO
public class SP_SearchEntity_Result
{
    public string ID { get; set; }
    public string NAME { get; set; }
}

//Businesslogic
public IQueryable Select(int PageIndex, int PageSize, List<KeyValuePair<string, string>> SearchBy, List<KeyValuePair<string, System.Data.SqlClient.SortOrder>> SortBy)
{
    SqlDatabase obj = (SqlDatabase)DatabaseFactory.CreateDatabase();//System.Configuration.ConfigurationManager.ConnectionStrings["MySqlServer"].ConnectionString
    return obj.ExecuteSprocAccessor<SP_SearchEntity_Result>("SP_SearchEntity", PageIndex, PageSize, SearchBy.ToDataTable(), SortBy.ToDataTable()).AsQueryable<SP_SearchEntity_Result>();
}

//Extension methods
public static DataTable ToDataTable(this List<KeyValuePair<string, string>> source)
{
    DataTable dataTable = new DataTable("Test");
    dataTable.Columns.Add("KEY",typeof(System.String));
    dataTable.Columns.Add("VALUE", typeof(System.String));

    foreach (KeyValuePair<string, string> data in source)
    {
        var dr = dataTable.NewRow();
        dr["KEY"] = data.Key;
        dr["VALUE"] = data.Value;
        dataTable.Rows.Add(dr);
    }

    return dataTable;
}

public static DataTable ToDataTable(this List<KeyValuePair<string, System.Data.SqlClient.SortOrder>> source)
{
    DataTable dataTable = new DataTable("Test");
    dataTable.Columns.Add("KEY", typeof(System.String));
    dataTable.Columns.Add("VALUE", typeof(System.String));

    foreach (KeyValuePair<string, System.Data.SqlClient.SortOrder> data in source)
    {
        var dr = dataTable.NewRow();
        dr["KEY"] = data.Key;
        dr["VALUE"] = data.Value == System.Data.SqlClient.SortOrder.Ascending ? "ASC" : "DESC";
        dataTable.Rows.Add(dr);
    }

    return dataTable;
}

存储过程返回结果中的两个表

SQL proc定义

CREATE TYPE KeyValueTableVariable AS TABLE
(
    [KEY] NVARCHAR(800),
    [VALUE] NVARCHAR(800)
)
GO
CREATE PROCEDURE SP_SearchEntity
@PageIndex INT=NULL,      
@PageSize INT=NULL,     
@SearchTableVar dbo.KeyValueTableVariable READONLY,
@SortTableVar dbo.KeyValueTableVariable READONLY 
AS
BEGIN
    /*Bla bla bla*/
    SELECT '1' as [ID], 'Nitin' as [NAME]
    SELECT '1' as [COUNT]
END

Answer 1

将表值参数传递给SQL Server有许多要求/限制。 例如，参见“将表值参数传递给存储过程”下的示例：

然后代码定义SqlCommand ，将CommandType属性设置为StoredProcedure 。 使用AddWithValue方法填充SqlParameter ，并将SqlDbType设置为Structured 。

请注意，仅使用AddWithValue是不够的 - 必须将SqlDbType更改为Structured 。

我相信 ExecuteSprocAccessor方法没有执行此更改（或者可能，如在其他一些示例中，其中TypeName必须设置为表类型的名称）。 我不能通过企业库源代码追逐这一切，但由于我在解决方案的任何地方都找不到“结构化”这个词，这就是我得出这个结论的原因。

因此，如果您想使用TVP，我认为您必须放弃企业库并使用SqlClient类型SqlClient编写数据访问代码。 （因为你正在使用TVP，你已经放弃了切换到不同RDBMS的可能性）。

Answer 2

我发现存储过程参数的xml数据类型更容易使用。 您可以将它们转换为XML，而不是将参数转换为DataTables，以用于以下示例：

CREATE PROCEDURE SP_SearchEntity
@PageIndex INT=NULL,      
@PageSize INT=NULL,     
@SearchTableVar xml=NULL,
@SortTableVar xml=NULL
AS
BEGIN
    /*Bla bla bla*/
    SELECT '1' as [ID], 'Nitin' as [NAME]
    SELECT '1' as [COUNT]
END

以下是KeyValuePair和查询的示例，在将其序列化为XML之后：

declare @sampleXml xml = '
<ArrayOfKeyValuePairOfstringstring xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/System.Collections.Generic">
  <KeyValuePairOfstringstring>
    <key>foo</key>
    <value>bar</value>
  </KeyValuePairOfstringstring>
  <KeyValuePairOfstringstring>
    <key>hello</key>
    <value>world</value>
  </KeyValuePairOfstringstring>
</ArrayOfKeyValuePairOfstringstring>'

select
        Node.Elem.value('*:key[1]', 'nvarchar(800)') as [Key]
        ,Node.Elem.value('*:value[1]', 'nvarchar(800)') as Value
    from @sampleXml.nodes(N'/*:ArrayOfKeyValuePairOfstringstring/*:KeyValuePairOfstringstring') Node(Elem)
go

和一个XML Serializer：

// from Plinqo: http://www.codesmithtools.com/product/frameworks
public static string ToXml<T>(this T item)
{
    var settings = new XmlWriterSettings();
    settings.Indent = true;
    settings.OmitXmlDeclaration = true;

    var sb = new System.Text.StringBuilder();
    using (var writer = XmlWriter.Create(sb, settings))
    {
        var serializer = new DataContractSerializer(typeof(T));
        serializer.WriteObject(writer, item);
    }

    return sb.ToString();
}

---

编辑：返回多个结果集并将它们绑定到对象

我将告诉你如何做到这一点，但我不确定这是你想做什么，基于你的模拟SQL。 如果您真的只是返回已返回对象的计数，则可以在IQueryable之后计算结果。

首先，您需要一种绑定对象的方法，您可以通过扩展MVC来获得这些方法。 这些模型绑定器希望您的查询返回与您的模型属性匹配的列名。

 using System; using System.Collections.Generic; using System.Web.Mvc; public partial class ModelBinder { /// <summary> /// Binds the values of an Dictionary to a POCO model /// </summary> public virtual T BindModel<T>(IDictionary<string, object> dictionary) { DictionaryValueProvider<object> _dictionaryValueProvider = new DictionaryValueProvider<object>(dictionary, null); return BindModel<T>(_dictionaryValueProvider); } /// <summary> /// Binds the values of an IValueProvider collection to a POCO model /// </summary> public virtual T BindModel<T>(IValueProvider dictionary) { Type _modelType = typeof(T); var _modelConstructor = _modelType.GetConstructor(new Type[] { }); object[] _params = new object[] { }; string _modelName = _modelType.Name; ModelMetadata _modelMetaData = ModelMetadataProviders.Current.GetMetadataForType(() => _modelConstructor.Invoke(_params), _modelType); var _bindingContext = new ModelBindingContext() { ModelName = _modelName, ValueProvider = dictionary, ModelMetadata = _modelMetaData }; DefaultModelBinder _binder = new DefaultModelBinder(); ControllerContext _controllerContext = new ControllerContext(); T _object = (T)_binder.BindModel(_controllerContext, _bindingContext); return _object; } } 

模型绑定的示例约定：

 public partial class Person { public int Id { get; set; } public string Name { get; set; } public Project Project { get; set; } public List<Person> Friends { get; set; } } public partial class Project { public int Id { get; set; } public string Name { get; set; } } select 1 as [Id] , 'NitinJs' as [Name] , 5 as [Project.Id] , 'Model Binding' as [Project.Name] , 2 as [Friends[0]].Id] , 'John' as [Friends[0]].Name] , 3 as [Friends[1]].Id] , 'Jane' as [Friends[1]].Name] 

现在，您需要一种方法来读取您的数据结果并将它们绑定到模型：

 /// <summary> /// Reads a record from a SqlDataReader, binds it to a model, and adds the object to the results parameter /// </summary> /// <typeparam name="T"></typeparam> /// <param name="reader"></param> /// <param name="modelName"></param> /// <param name="results"></param> private void ReadAs<T>(SqlDataReader reader, string modelName, List<T> results, string commandText) { Dictionary<string, object> _result = new Dictionary<string, object>(); for (int i = 0; i < reader.FieldCount; i++) { string _key = modelName + "." + reader.GetName(i); object _value = reader.GetValue(i); if (_result.Keys.Contains(_key)) // Dictionaries may not have more than one instance of a key, but a query can return the same column twice { // Since we are returning a strong type, we ignore columns that exist more than once. throw new Exception("The following query is returning more than one field with the same key, " + _key + ": " + commandText); // command.CommandText } _result.Add(_key, _value); } T _object = new ModelBinder().BindModel<T>(_result); if (_object != null) { results.Add((T)_object); } } 

接下来，您需要一种与数据库建立开放连接的方法（注意：您可能希望从配置中获取_dbConnectionString）：

 public SqlConnection GetOpenConnection() { _sqlConnection = new SqlConnection(_dbConnectionString); _sqlConnection.Open(); return _sqlConnection; } 

最后，您需要连接到数据库以获取结果集：

 /// <summary> /// Executes a SqlCommand that expects four result sets and binds the results to the given models /// </summary> /// <typeparam name="T1">Type: the type of object for the first result set</typeparam> /// <typeparam name="T2">Type: the type of object for the second result set</typeparam> /// <returns>List of Type T: the results in a collection</returns> public void ExecuteAs<T1, T2>(SqlCommand command, List<T1> output1, List<T2> output2) { string _modelName1 = typeof(T1).Name; string _modelName2 = typeof(T2).Name; string _commandText = command.CommandText; using (SqlConnection connection = GetOpenConnection()) { using (command) { command.Connection = connection; command.CommandTimeout = _defaultCommandTimeout; using (SqlDataReader reader = command.ExecuteReader()) { while (reader.Read()) // Call Read before accessing data. { ReadAs<T1>(reader, _modelName1, output1, _commandText); } reader.NextResult(); while (reader.Read()) // Call Read before accessing data. { ReadAs<T2>(reader, _modelName2, output2, _commandText); } } // end using reader } // end using command } // end using connection } 

然后你的select方法看起来更像这样：

 public void SelectInto<SP_SearchEntity_Result, int>(int PageIndex, int PageSize, List<KeyValuePair<string, string>> SearchBy, List<KeyValuePair<string, System.Data.SqlClient.SortOrder>> SortBy, List<<SP_SearchEntity_Result> result1, List<int> result2) { SqlCommand command = new SqlCommand("SP_SearchEntity"); command.CommandType = System.Data.CommandType.StoredProcedure; command.Parameters.Add("PageIndex", SqlDbType.Int).Value = PageIndex; command.Parameters.Add("SearchTableVar", SqlDbType.Xml).Value = SearchBy.ToXml(); List<KeyValuePair<string, string>> SortByCastToString = // modify your ToDataTable method so you can pass a List<KeyValuePair<string, string>> for SortBy command.Parameters.Add("SortTableVar", SqlDbType.Xml).Value = SortByCastToString.ToXml(); ExecuteAs<SP_SearchEntity_Result, int>(command, result1, result2); } public void SomeCallingMethod() { List<SP_SearchEntity_Result> _results = new List<SP_SearchEntity_Result>{}; List<int> _counts = new List<int>{}; // ... // setup your SearchBy and SortBy // ... SelectInto<SP_SearchEntity_Result, int>(1, 20, SearchBy, SortBy, _results, _counts); } 

Answer 3

使用企业库数据访问应用程序块v6.0.1304，TVP作为存储过程的参数对我来说很有用。 我的C＃代码如下所示：

public static DataSet SomeHelperMethod(DataTable tvp1, DataTable tvp2)
{
    DbCommand cmd = <SqlDatabase>.GetStoredProcCommand("StoredProcName");

    SqlParameter p1 = new SqlParameter("@p1", tvp1);
    p1.SqlDbType = SqlDbType.Structured;
    cmd.Parameters.Add(p1);

    SqlParameter p2= new SqlParameter("@p2", tvp2);
    p2.SqlDbType = SqlDbType.Structured;
    cmd.Parameters.Add(p2);

    return <SqlDatabase>.ExecuteDataSet(cmd);
}