c# - 在OracleCommand INSERT INTO之后如何检索sys_guid（）的值

尝试returning .. into 条款如

   ...

   using (OracleCommand cmd = connection.CreateCommand()) {
     cmd.CommandText = 
       @"INSERT INTO CUSTOMERS (
           NAME,
           DETAILS) 
         VALUES (
           :nm, 
           :dts)
         RETURNING 
           ""ORDER"" INTO :orderid";

     cmd.Parameters.Add("nm", OracleDbType.VarChar);
     cmd.Parameters["nm"].Value = name;
     cmd.Parameters.Add("dts", OracleDbType.VarChar);
     cmd.Parameters["dts"].Value = details;

     cmd.Parameters.Add("orderid", OracleDbType.VarChar);  
     cmd.Parameters["orderid"].Direction = ParameterDirection.Output;

     try {
       cmd.ExecuteNonQuery(); // Just execute, nothing to read
       transaction.Commit(); 

       guid = Convert.ToString(cmd.Parameters["orderid"].Value);
     }
     catch (Exception e) { //TODO: put more specific exception type
       transaction.Rollback();   
       Console.WriteLine(e.Message);     
     } 

     return guid;
   }  

   ...