How to get the values from the resultset???

Question

I have a problem with this code given below,
i am executing an sql query which return a union of values from two tables.
the problem here is how do i read the values from the resultset.
here is the code....
package com.webserver;
import java.sql.*;
public class UnionDemo{
public static void main(String args[]){
Connection connection =null;
Statement statement =null;
ResultSet rs =null;
try{
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
connection = DriverManager.getConnection("jdbc:oracle:thin:@:1521:ORCL","scott","tiger");
statement = con.createStatement();
rs = statement.executeQuery("(select tablename from node where appid=432) union (select tablename from uomnode where appid=432)");
ResultSetMetaData rsmd = rs.getMetaData();
int numberOfColumns = rsmd.getColumnCount();
while (rs.next()){
System.out.println(rs.getString(1));
// instead of rs.getString(1) I also used rs.getString("tablename") but of no success....
}//end of while
}catch(Exception exp){
exp.printStackTrace();
finally{
try{
if (rs!=null) rs.close();
if (statement!=null) statement.close();
if (con!=null) con.close();
}catch(Exception exp1){
exp1.printStackTrace();
}//end of finally
}//end of main
}//end of class
when i execute this program i get an oracle error ORA-01009
which says (java.sql.SQLException: ORA-01009: missing mandatory parameter)
can anyone help to retrieve the values from this resultset...
thanx

Answer 1

[cut]
i am executing an sql query which return a union of
values from two tables.
the problem here is how do i read the values from the
resultset.[cut]
When the error occours?
1) Executing query ?
2) Retrieving the field from the resultSet ?
3) ecc. ?
BTW, first of all, try to execute the query removing the parenthesis
of the two select statement. I know that there are some problem
with the oracle jdbc driver about them.
Hope it helps.