Data access: Data stored in databases must be accessible efficiently. Very large databases, such as those maintained by eBay, have to be managed in a way that when users search within them, their results should be available within a matter of seconds. A search in eBay results in a response within a few seconds, even though the system has to search through billions of records. Furthermore, the response from the database has to be presented to the user in a manner that is easy to read and understand which requires further processing.