我正在构建一个接口，该接口将通过我的.NET Winforms应用程序从Oracle数据库运行存储过程。我能够成功连接到Oracle数据库，并且可以成功地使用ODP.NET API来检索所有存储过程的列表以及我选择的任何存储过程的所有参数。
当我尝试运行存储过程时存在问题。当我尝试执行并返回Oracle错误告诉我没有记录时它会中断，但是当我从sql developer运行存储过程时，它会返回我正在寻找的内容。这是存储过程：
create or replace procedure sp_get_emp_info
(
empid in INTEGER,
m_UserName out VARCHAR2,
m_Email out VARCHAR2,
m_IsActive out INTEGER
) as
begin
SELECT
UserName,
Email,
IsActive
INTO
m_UserName,
m_Email,
m_IsActive
FROM
MICHAELTABLE
WHERE ID = empid;
end sp_get_emp_info;
这是我写的一个测试类，试图在C＃中读取它：
using Oracle.ManagedDataAccess.Client;
using System;
namespace OracleTester
{
class Program
{
static void Main(string[] args)
{
OracleConnection conn = new OracleConnection();
conn.ConnectionString = "User Id=apps;Password=apps;Data Source=(DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = Orchid64)(PORT = 1521))(CONNECT_DATA = (SERVICE_NAME = MVP)));";
Console.BackgroundColor = ConsoleColor.Black;
Console.ForegroundColor = ConsoleColor.DarkYellow;
//string procs = "SELECT object_name FROM dba_objects WHERE object_type = 'PROCEDURE' AND owner = 'APPS'";
//OracleCommand cmd = new OracleCommand(procs, conn);
//cmd.CommandType = System.Data.CommandType.Text;
//cmd.Connection.Open();
//OracleDataReader reader = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
//int i = 1;
//while (reader.Read())
//{
// Console.WriteLine(i + ". " +reader.GetString(0));
// i++;
//}
OracleCommand comm = new OracleCommand();
comm.CommandText = "SP_GET_EMP_INFO";
comm.CommandType = System.Data.CommandType.StoredProcedure;
comm.Connection = conn;
OracleParameter user = new OracleParameter("m_UserName", OracleDbType.Varchar2, 25);
user.Direction = System.Data.ParameterDirection.Output;
OracleParameter email = new OracleParameter("m_Email", OracleDbType.Varchar2, 50);
email.Direction = System.Data.ParameterDirection.Output;
OracleParameter active = new OracleParameter("m_IsActive", OracleDbType.Double, 38);
active.Direction = System.Data.ParameterDirection.Output;
comm.Parameters.Add(user);
comm.Parameters.Add(email);
comm.Parameters.Add(active);
OracleParameter empID = new OracleParameter("empid", OracleDbType.Double, 38);
empID.Direction = System.Data.ParameterDirection.Input;
empID.SourceColumn = "empid";
empID.Value = 1;
comm.Parameters.Add(empID);
comm.Connection.Open();
OracleDataReader rdr = comm.ExecuteReader();
while (rdr.Read())
{
Console.WriteLine(rdr["m_UserName"].ToString());
}
Console.WriteLine("Server Version: " + conn.ServerVersion);
conn.Dispose();
Console.ReadLine();
}
}
}
当我尝试运行它时，这是我收到的例外：
Oracle.ManagedDataAccess.Client.OracleException was unhandled
DataSource=""
ErrorCode=-2147467259
HResult=-2147467259
IsRecoverable=false
Message=ORA-01403: no data found
ORA-06512: at "APPS.SP_GET_EMP_INFO", line 9
ORA-06512: at line 1
Number=1403
Procedure=""
Source=Oracle Data Provider for .NET, Managed Driver
StackTrace:
at OracleInternal.ServiceObjects.OracleCommandImpl.VerifyExecution(OracleConnectionImpl connectionImpl, Int32& cursorId, Boolean bThrowArrayBindRelatedErrors, OracleException& exceptionForArrayBindDML, Boolean& hasMoreRowsInDB, Boolean bFirstIterationDone)
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, OracleException& exceptionForArrayBindDML, Boolean isDescribeOnly, Boolean isFromEF)
at Oracle.ManagedDataAccess.Client.OracleCommand.ExecuteReader(Boolean requery, Boolean fillRequest, CommandBehavior behavior)
at Oracle.ManagedDataAccess.Client.OracleCommand.ExecuteReader()
at OracleTester.Program.Main(String[] args) in C:\TestProjects\OracleTester\OracleTester\Program.cs:line 54
at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException:
非常感谢任何帮助!!
答案 0 :(得分：2)
默认情况下， OracleCommand.CommandType = Text 命令的ODP.NET参数按位置绑定。 OracleCommand 类提供 BindByName 属性 - 将此属性设置为true以按名称而不是按位置绑定参数。
您正在创建命名参数，但它们实际上是按位置添加的，这意味着您有效地为m_IsActive提供了值（尽管它是一个OUT参数）并且保留empid null ，就程序而言。
您可以将comm.BindByName=true设置为@b_levitt在评论中指出。或者，如果您重新排序参数赋值以匹配形式参数顺序，它将选择正确的值：
OracleParameter empID = new OracleParameter("empid", OracleDbType.Double, 38);
empID.Direction = System.Data.ParameterDirection.Input;
empID.SourceColumn = "empid";
empID.Value = 1;
comm.Parameters.Add(empID);
comm.Parameters.Add(user);
comm.Parameters.Add(email);
comm.Parameters.Add(active);
comm.Connection.Open();
OracleDataReader rdr = comm.ExecuteReader();
当CommandType属性设置为StoredProcedure时，documentation似乎不清楚返回值将包含什么，如果您正在调用函数，它可能会有用;但是通过过程调用没有关联的结果集，所以这可能是空的。在它上面循环找不到任何东西：
while (rdr.Read())
{
Console.WriteLine(rdr["m_UserName"].ToString());
}
相反，您可以直接引用OUT参数的值：
Console.WriteLine(user.value);