Free Oracle Essentials Oracle Database 11g by Rick Greenwald

an HTML-based tool for developing web-enabled applications and content-driven web sites. Portal application systems are developed and deployed in a simple browser environment. Portal includes wizards for developing application components incorporating “servlets” and access to other HTTP web sites. Portals can be designed to be user-customizable and are deployed to the middle-tier Oracle Application Server.
    Oracle Portal brought a key enhancement to WebDB, the ability to create and use portlets , which allow a single web page to be divided up into different areas that can independently display information and interact with the user. For example, Oracle Answers, Discoverer, and Reports can be accessed as portlets.
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    Chapter 1: Introducing Oracle

    Oracle’s next generation portal framework product, introduced in 2006, and initially made available as an Application Server option is WebCenter.
    Embedded Databases
    Although Oracle’s database family can be deployed for embedded applications, the footprint and functionality might be more than what you need. Today, Oracle offers other embedded databases including TimesTen, Berkeley DB, and Oracle Database Lite. These database engines have unique code lines in order to provide small footprints and have different intended roles. For this reason, we will describe these briefly in the following subsections but will not explore their capabilities in great detail elsewhere in this book.
    Oracle TimesTen
    Oracle TimesTen is a relational database that is stored in physical memory and is typically used where very high-performance transaction-processing workloads are present. Access to the TimesTen database is available through SQL, JDBC, JMS, and ODBC. TimesTen databases can be deployed as exclusive or shared and can be created as permanent or temporary.
    The database is refreshed by gathering data using TimesTen libraries deployed to applications or by using a Cache Connect option to an Oracle database. Because data is read and updated in memory, average update or read response times are typically measured in the millionths of seconds. The Cache Connect option supports both read and write caching of Oracle database data. Updates can be bidirectional between TimesTen and Oracle.
    As is typical for embedded databases, TimesTen requires almost no ongoing administration. Replication is possible from one TimesTen database to another through an option and is, by default, asynchronous.
    Oracle Berkeley DB
    Oracle Berkeley DB is an extremely small-footprint embedded database engine providing record-level locking. It comes in Java and XML versions. It is designed to be deployed with and run in the same process as your applications. When Berkeley DB
    is deployed in this manner, no separate database administration is required. Footprints for the database can be as small as 400 KB.
    The Java Edition of Berkeley DB supports the Java Transaction API (JTA), J2EE
    Connector Architecture (JCA), and Java Management Extensions (JMX). The database is a single JAR file that is 820 KB in size and runs in the same Java Virtual Machine (JVM) as the application. A Direct Persistence Layer (DPL) is supported for accessing Java objects.
    Embedded Databases
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    The XML Edition of Berkeley DB is most commonly used in network-based applications where content is managed. XQuery and XPath are supported.
    Both editions can be configured for high availability using replication. Automatic recovery is also supported. Deployment decisions such as these are made by the application designer at application design time.
    Oracle Lite
    Oracle Lite is a suite of products enabling mobile use of database-centric applications. Key components of Oracle Lite include the Oracle Lite Database, Mobile Development Kit, and Mobile Server (an extension of the Oracle Application Server).
    The Oracle Lite Database engine requires a 50KB to 1 MB footprint depending on the platform. Applications written using Mobile SQL, C++, and