Example: Reading a table

In this example, a PreparedStatement object is obtained from a connection, and a ResultSet object is obtained from the PreparedStatement. The next method on the ResultSet returns true each time a subsequent row can be obtained. Values for the columns in the current row can then be obtained from the ResultSet object.

♦ To run the ReadSeq.java example

Change to the following directory: samples-dir\UltraLiteJ.

For information about the default location of samples-dir, see Samples directory.
Run the CreateDb example:
rundemo CreateDb
See Example: Creating a database.
Run the LoadDb example:
rundemo LoadDb
See Example: Inserting rows.
Run the following command (the command is case sensitive):
rundemo ReadSeq

Notes

When a ResultSet is created, it is positioned before the first row of the result set. The code must invoke the next method to move to the first row in the table.
Table and column names in UltraLiteJ are case insensitive. Columns can be referenced either by the column name alone ("age") or by qualifying the column name with the table name ("Employee.age").

// *****************************************************
// Copyright (c) 2006-2010 iAnywhere Solutions, Inc.
// Portions copyright (c) 2006-2010 Sybase, Inc.
// All rights reserved. All unpublished rights reserved.
// *****************************************************
// This sample code is provided AS IS, without warranty or liability
// of any kind.
//
// You may use, reproduce, modify and distribute this sample code
// without limitation, on the condition that you retain the foregoing
// copyright notice and disclaimer as to the original iAnywhere code.
//
// *********************************************************************
package com.ianywhere.ultralitej.demo;

import com.ianywhere.ultralitej12.*;

/**
 * ReadSeq -- sample program to demonstrate reading a Database table
 * sequentially.
 */
public class ReadSeq
{
    /**
     * mainline for program.
     *
     * @param args command-line arguments
     *
     */
    public static void main
	( String[] args )
    {
	try {
	    Configuration config = DatabaseManager.createConfigurationFile( "Demo1.ulj" );
	    Connection conn = DatabaseManager.connect( config );
	    PreparedStatement stmt = conn.prepareStatement( "SELECT * FROM Employee ORDER BY number" );
	    ResultSet cursor = stmt.executeQuery();
	    for( ; cursor.next(); ) {
		int emp_no = cursor.getInt( 1 /* "number" */ );
		String last_name = cursor.getString( "last_name" );
		String first_name = cursor.getString( 3 /* "first_name" */ );
		int age = cursor.getInt( 4 /* "age" */ );
		Demo.display( first_name + ' ' + last_name );
		Demo.display( "  empl. no = "
			    , Integer.toString( emp_no )
			    , "  age = "
			    , Integer.toString( age ) );
	    }
	    cursor.close();
	    stmt.close();
	    conn.release();
	} catch( ULjException exc ) {
	    Demo.displayException( exc );
	}
    }
}

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