DataBaseMetadata.getAttributes - Problem with Exception

Question

I am Using Oracle 10g and have an exception when I run this code:
public void getAttributes(String schema, String type){
     try{
          md=conn.getMetaData();
          rs=md.getAttributes(null,"SYSTEM","TABLE1", null);
          while(rs.next()){
               System.out.println(rs.getString("ATTR_NAME"));
     }catch(SQLException ex){
          System.out.println(ex.getSQLState());
          System.out.println(ex.getErrorCode());
          System.out.println(ex);
The Error code which is written by System.out.println(ex), it might be in greek font and doesn't appear in distinguishable font, so I can't understand in what the error refers to.
The ex.getSQLState() has the value null
and
the ex.getErrorCode() has the value 17023
I try it and the exception is triggered in this line:
rs=md.getAttributes(null,"SYSTEM","TABLE1", null);
Can someone help me with what this problem might be?

Answer 1

If you want to use a JDBC standard technique and don't want to query Oracle's dictionary tables (such as USER_TABLES or ALL_TABLES), then your choices are pretty much DatabaseMetaData and ResultSetMetaData.
In my limited experience, both of these work fine on Oracle 10g; I don't understand why you're having problems.
You might try testing against a different schema, something other than SYSTEM. SYSTEM is special, and it wouldn't surprise me if it was different here. Also, SYSTEM should never ever ever be used for anything but Oracle's own database objects; if you have used SYSTEM for your own things, I would encourage you to reinstall your database, or at least to stop immediately. Also, your programs should never connect to the database as the SYSTEM user; only DBAs shuld use this account for the (very rare) upgrade and maintenance tasks that require it; most DBA tasks should be done from a seperate account that has been granted the DBA role.