//*********************************************************************
//
//                 Copyright (c) 2004-2008 by Teradata Corporation
//                         All Rights Reserved
//
//*********************************************************************
//
//  File:       T20101JD.java
//  Header:     none
//  Purpose:    Demonstrate the JDBC API for retrieving statement
//              result set meta data.
//              The program will:
//                -  Connect as user guest/please
//                -  Prepare an SQL statement
//                -  Obtain result set meta data
//                -  Disconnect.
//
//  JDBC API: java.sql.Connection,
//            java.sql.Statement, java.sql.Statement.executeQuery,
//            java.sql.ResultSet, java.sql.ResultSet.getMetaData,
//            java.sql.ResultSetMetaData
//
//  Version: Updated for Teradata V2R6
//
//*********************************************************************

import java.sql.*;

public class T20101JD
{
    // Name of the user able to create, drop, and manipulate tables
    public static String sUser = "guest";
    public static String sPassword = "please";

    public static void main(String args[])
    throws ClassNotFoundException
    {
        // Creation of URL to be passed to the JDBC driver
        String url = "jdbc:teradata://whomooz/TMODE=ANSI,CHARSET=UTF8";

        // Query statement selecting all columns of the table. Using this query,
        // column metadata can be retrieved.
        String sSelAll = " SELECT * FROM employee2";

        try
        {
            System.out.println("\n Sample T20101JD: \n");
            System.out.println(" Looking for the Teradata JDBC driver... ");
            // Loading the Teradata JDBC driver
            Class.forName("com.teradata.jdbc.TeraDriver");
            System.out.println(" JDBC driver loaded. \n");

            // Attempting to connect to Teradata
            System.out.println(" Attempting to connect to Teradata via" +
                               " the JDBC driver...");

            // Creating a connection object
            Connection con = DriverManager.getConnection(url, sUser, sPassword);
            System.out.println(" User " + sUser + " connected.");
            System.out.println(" Connection to Teradata established. \n");

            try
            {
                // Creating a statement object from an active connection
                Statement stmt = con.createStatement();
                System.out.println(" Statement object created. \n");

                try
                {
                    // Create a ResultSet object representing the data
                    // resulting from the query
                    ResultSet rset = stmt.executeQuery(sSelAll);
                    // Create a ResultSetMetaData object that allows
                    // meta data information retrieval about the query result
                    ResultSetMetaData rsmd = rset.getMetaData();

                    // Retrieve the number of columns returned
                    int colCount = rsmd.getColumnCount();
                    System.out.println(" This table has " + colCount + " columns.\n");

                    // For every column, display it's information.
                    System.out.println(" Displaying column information: ");

                    int i = 1;     // Initialize loop counter
                    while(i <= colCount)
                    {
                        // This code will demonstrate all available methods for
                        // retrieving column meta data.

                        System.out.println();
                        System.out.println(" Column " + i);
                        System.out.println(" ------------ ");
                        // Display the suggested column title for use in
                        // printouts and displays
                        System.out.println(" Column label: "
                                           + rsmd.getColumnLabel(i));
                        // Display the column name
                        System.out.println(" Column name: "
                                           + rsmd.getColumnName(i));
                        // Display the SQL type of a column.
                        System.out.println(" Column type: "
                                           + rsmd.getColumnType(i));
                        // Display the type name of a column
                        System.out.println(" Column type name: "
                                           + rsmd.getColumnTypeName(i));
                        // Display information on whether NULL values are allowed
                        System.out.println(" NULLs allowed: "
                                           + rsmd.isNullable(i));
                        // Display the normal maximum width of a column in characters.
                        System.out.println(" Maximum character width: "
                                           + rsmd.getColumnDisplaySize(i));
                        // Display precision: the number of decimal digits
                        // Note: default value is 0.
                        System.out.println(" Column precision"
                                           + " (number of decimal places): "
                                           + rsmd.getPrecision(i));
                        // Display the number of digits to the right of the
                        // decimal point. Note: default value is 0.
                        System.out.println(" Precision to the right of"
                                           + " the decimal point: "
                                           + rsmd.getScale(i));
                        // Increment column counter
                        i++;
                    }
                }
                finally
                {
                    // Close the statement
                    stmt.close();
                    System.out.println("\n Statement object closed. \n");
                }
            }
            finally
            {
                // Close the connection
                System.out.println(" Closing connection to Teradata...");
                con.close();
                System.out.println(" Connection to Teradata closed. \n");
            }

            System.out.println(" Sample T20101JD finished. \n");
        }
        catch (SQLException ex)
        {
            // A SQLException was generated.  Catch it and display
            // the error information. Note that there could be multiple
            // error objects chained together.
            System.out.println();
            System.out.println("*** SQLException caught ***");

            while (ex != null)
            {
                System.out.println(" Error code: " + ex.getErrorCode());
                System.out.println(" SQL State: " + ex.getSQLState());
                System.out.println(" Message: " + ex.getMessage());
                ex.printStackTrace();
                System.out.println();
                ex = ex.getNextException();
            }

            throw new IllegalStateException ("Sample failed.") ;
        }
    } // End main
} // End class T20101JD