我正在尝试创建一个测试应用程序，该应用程序将向Oracle存储过程传递一个对象数组（在我的示例中为Employees）。
当我调用ExecuteReader来调用该过程时，收到错误
列包含NULL数据
但我不知道那是什么意思。
下面是我使用的代码。我有以下类：

[OracleCustomTypeMapping("EMTEST")]
public class Employee : IOracleCustomType, INullable
{

    public Employee(int? Id, string Name)
    {
        this.Id = Id;
        this.Name = Name;
    }

    [OracleObjectMapping("Name")]
    public string Name { get; set; }

    [OracleObjectMapping("Id")]
    public int? Id { get; set; }

    public bool IsNull { get; set; }

    public static Employee Null => new Employee(0, "") { IsNull = true };

    public void FromCustomObject(OracleConnection con, object udt)
    {
        OracleUdt.SetValue(con, udt, "Id", Id);
        OracleUdt.SetValue(con, udt, "Name", Name);
    }

    public void ToCustomObject(OracleConnection con, object udt)
    {
        Id = ((int?)(OracleUdt.GetValue(con, udt, "Id")));
        Name = ((string)(OracleUdt.GetValue(con, udt, "Name")));
    }
}

在oracle端，我创建一个类型：

create or replace TYPE EMTEST AS OBJECT
(
     Id number  null,
     Name varchar2(50)  null    
);

以及一个名为PKS_CARAT的程序包中的过程
这是标题（在其中定义类型的表格）：

type T_EMTEST_ARRAY is table of EMTEST;

procedure TestGetObjectsBack(
        Employes in T_EMTEST_ARRAY,
        ResultTest OUT RC_Result
);

这是身体：

procedure TestGetObjectsBack(
        Employes in T_EMTEST_ARRAY,
        ResultTest OUT RC_Result
)
is
    
begin

OPEN ResultTest FOR
select 1 as Id,'mika' as Name from dual;

-- select e.Id,e.Name from table (Employes) e;
    
end TestGetObjectsBack;

以下是调用存储过程的代码：

var oracleConnection = new OracleConnection("User Id=xxx;Password=xxx;Data Source=ORAKISDEV2;Connection Lifetime=10;Min Pool Size=1;Max Pool Size=200;");

var employeList = new List<Employee>()
{
    new Employee(1,"Zoki"),
    new Employee(2, "Pera"),
};

var employeArray = employeList.ToArray();

var employeParam = new OracleParameter("Employes", OracleDbType.Object,  ParameterDirection.Input);
employeParam.CollectionType = OracleCollectionType.PLSQLAssociativeArray;

employeParam.Size = employeArray.Length;
employeParam.UdtTypeName = "PKS_CARAT.T_EMTEST_ARRAY";
employeParam.Value = employeArray;

var cursor = new OracleParameter("ResultTest", OracleDbType.RefCursor, ParameterDirection.Output);

oracleConnection.Open();
using (var oracleCommand = oracleConnection.CreateCommand())
{
    oracleCommand.Connection = oracleConnection;
    oracleCommand.CommandText = "PKS_CARAT.TestGetObjectsBack";
    oracleCommand.CommandType = CommandType.StoredProcedure;
    oracleCommand.BindByName = true;

    oracleCommand.Parameters.Add(employeParam);
    oracleCommand.Parameters.Add(cursor);

var reader = oracleCommand.ExecuteReader();
....

我读了很多文章，最重要的有：

1. pass array of objects to oracle stored procedure using ODP.Net managed client
2. Why do I get "Invalid Parameter binding" when using Oracle stored procedure with Udt and C#
   我尝试了许多建议，但没有任何不同。我仍然得到列包含空数据，没有任何解释哪个数据为空或为什么会导致此问题。我检查了类中的列和oracle类型中的列是否相同，看起来它们是相同的。
   完整的例外文本为：* “列包含NULL数据”。来自“Oracle. ManagedDataAccess”*
   异常的类型为系统.InvalidCastException
   我正在使用nuget软件包Oracle.管理数据访问.核心版本3.21.80
   下面是异常的堆栈顶部跟踪：

OracleInternal.UDT.Types.UDTNamedType.GetNamedTypeMetaData(OracleConnection conn, OracleCommand getTypeCmd)
   at OracleInternal.UDT.Types.UDTTypeCache.GetMetaData(OracleConnection conn, UDTNamedType udtType)
   at OracleInternal.UDT.Types.UDTTypeCache.CreateUDTType(OracleConnection conn, String schemaName, String typeName)
   at OracleInternal.UDT.Types.UDTTypeCache.GetUDTType(OracleConnection conn, String schemaName, String typeName)
   at OracleInternal.ConnectionPool.OraclePoolManager.GetUDTType(OracleConnection conn, String schemaName, String typeName)
   at Oracle.ManagedDataAccess.Client.OracleConnection.GetUDTTypeFromCache(String schemaName, String typeName)
   at Oracle.ManagedDataAccess.Client.OracleParameter.GetUDTType(OracleConnection conn)
   at Oracle.ManagedDataAccess.Client.OracleParameter.PreBind_UDT(OracleConnection conn)
   at Oracle.ManagedDataAccess.Client.OracleParameter.PreBind(OracleConnectionImpl connImpl, ColumnDescribeInfo cachedParamMetadata, Boolean& bMetadataModified, Int32 arrayBindCount, ColumnDescribeInfo& paramMetaData, Object& paramValue, Boolean isEFSelectStatement, SqlStatementType stmtType)
   at OracleInternal.ServiceObjects.OracleCommandImpl.InitializeParamInfo(ICollection paramColl, OracleConnectionImpl connectionImpl, ColumnDescribeInfo[] cachedParamMetadata, Boolean& bMetadataModified, Boolean isEFSelectStatement, MarshalBindParameterValueHelper& marshalBindValuesHelper)
   at OracleInternal.ServiceObjects.OracleCommandImpl.ProcessParameters(OracleParameterCollection paramColl, OracleConnectionImpl connectionImpl, ColumnDescribeInfo[] cachedParamMetadata, Boolean& bBindMetadataModified, Boolean isEFSelectStatement, MarshalBindParameterValueHelper& marshalBindValuesHelper)
   at OracleInternal.ServiceObjects.OracleCommandImpl.ExecuteReader(String commandText, OracleParameterCollection paramColl, CommandType commandType, OracleConnectionImpl connectionImpl, OracleDataReaderImpl& rdrImpl, Int32 longFetchSize, Int64 clientInitialLOBFS, OracleDependencyImpl orclDependencyImpl, Int64[] scnForExecution, Int64[]& scnFromExecution, OracleParameterCollection& bindByPositionParamColl, Boolean& bBindParamPresent, Int64& internalInitialLOBFS, Int64 internalInitialJSONFS, OracleException& exceptionForArrayBindDML, OracleConnection connection, IEnumerable`1 adrianParsedStmt, Boolean isDescribeOnly, Boolean isFromEF)
   at Oracle.ManagedDataAccess.Client.OracleCommand.ExecuteReader(Boolean requery, Boolean fillRequest, CommandBehavior behavior)
   at Oracle.ManagedDataAccess.Client.OracleCommand.ExecuteReader()
   at OracleArrayTest.Program.TestCollectionCustom() in C:\project\BulkProject\OracleArrayTest\Program.cs:line 203

有人知道我做错了什么吗？这个异常告诉我什么？