C＃使用ODBC连接到Oracle

Question

I am trying to connect to a remote Oracle database using ODBC in c#.

i make a test code for reproduce de error

String sql = "SELECT * FROM ALL_TABLES";
        OdbcConnection conn = new OdbcConnection();
        conn.ConnectionString = "Driver={Oracle in instant_client_12};Server=192.168.56.101;Uid=SYS;Pwd=somepassword;";
        conn.Open();

        OdbcCommand command = conn.CreateCommand();
        command.CommandText = sql;
        System.Data.DataTable dt = new System.Data.DataTable();
        OdbcDataAdapter da = new OdbcDataAdapter(command);
        da.Fill(dt);
        conn.Close();

        Console.WriteLine("Filas: "+dt.Rows.Count);
        Console.ReadKey();

and i get the next error in 4th line, conn.Open()

ERROR [HY000] [Oracle][ODBC][Ora]ORA-12560: TNS:protocol adapter error

ERROR [IM006] [Microsoft][Administrador de controladores ODBC] Error de SQLSetConnectAttr del controlador
ERROR [HY000] [Oracle][ODBC][Ora]ORA-12560: TNS:protocol adapter error

sqlplus works fine

sqlplus.exe SYSTEM/somepassword@PRUEBA

SQL*Plus: Release 12.1.0.2.0 Production on Thu Mar 26 19:45:37 2015

Copyright (c) 1982, 2014, Oracle. All rights reserved.

And PRUEBA = 192.168.56.101, setted in tnsname.ora

Any body have idea of what happens? i need some help. Thank you for your time

Answer 1

See your connection string:

    conn.ConnectionString = "Driver={Oracle in instant_client_12};Server=192.168.56.101;Uid=SYS;Pwd=somepassword;";

You don't specify any database name, just a server. A server may host several Oracle DB's.

Try one of the following

    conn.ConnectionString = "Driver={Oracle in instant_client_12};DBQ=PRUEBA;Uid=SYS;Pwd=somepassword;";

    conn.ConnectionString = "Driver={Oracle in instant_client_12};CONNECTSTRING=PRUEBA;Uid=SYS;Pwd=somepassword;";

    conn.ConnectionString = "Driver={Oracle in instant_client_12};Server=PRUEBA;Uid=SYS;Pwd=somepassword;";