On Your Marks ... Get Set ... Go!!!: An Introduction to the Apache Derby and IBM Cloudscape Community
- Let Me Get This Straight, Apache Derby Is IBM Cloudscape?
- Development of the Apache Derby Database—Who Can Contribute and How?
- How Can IBM Sell a Product for Profit and Contribute the Same Product to the Open Source Community?
- How an Open Source Database Like Apache Derby Can Help
- Why the Need for a Local Data Store?
- Why Use a Relational Database?
- How the Apache Derby Platform Can Help Your Business
- A High-Level View of the Apache Derby Database
- The Apache Derby Components
- Developing Apache Derby Applications
Welcome to the Apache Derby and IBM Cloudscape family! We are glad to have you join our community of thousands, all dedicated to open standards and open source computing.
On August 3, 2004, IBM released a technical preview of IBM Cloudscape Version 10. While this in itself is exciting news, more importantly, IBM also made one of the most significant contributions in the history of the open source database community by contributing the source code for IBM Cloudscape to the Apache Software Foundation as the Apache Derby database. The Apache Software Foundation subsequently accepted Apache Derby as an incubator project. At the time this book was published, Apache Derby and IBM Cloudscape Version 10.1 was released and the Apache Derby project graduated from an incubator project (more on that in a bit) to an Apache sub-project.
The history of the Cloudscape technology is an interesting one indeed. In 1997, Cloudscape Inc. released what was perhaps the world’s first real Java-based database, well before Java became the darling of the information technology (IT) community. The Cloudscape database began to carve its reputation as a pure Java-based relational database with just a 2 MB "fingerprint" that simplified application development. It made applications easier to deploy on any platform and represented the first truly relational database for which a DBA was not a requirement! Its significance went well beyond a "lights out" no management database. Cloudscape opened the doors for application developers (who are not generally database savvy) to leverage the benefits of a persistent data store for their applications.
In 1999, Informix bought Cloudscape Inc. and continued to enhance this database server, seeding it with even richer self-managing, ease of deployment, and open standards features—many of which were ahead of their time. IBM acquired the Cloudscape technology in July 2001 by purchasing the assets of Informix Software. As you can see, the IBM Cloudscape (formerly just Cloudscape) database has been around for a long time, which accounts for its maturity, robustness, and functionally rich feature set.
After the Informix acquisition, the IBM Cloudscape development teams have reported into IBM’s Database Technology Institute, under the direction of Don Haderle and Dr. Patricia Selinger, two of the founders of relational database technology. In fact, since IBM acquired this technology, it has funded a continually expanding development team through several new versions and added compatibility with the IBM DB2 Universal Database (DB2 UDB) family through a fully compliant SQL application programming interface (API). This means that applications written for IBM Cloudscape (and subsequently Apache Derby—more on that in a bit) can easily be migrated to the DB2 UDB platform if necessary.
You might be surprised to know just how many partners, customers, and software packages use IBM Cloudscape in their technology—the very technology you’re about to learn how to program to. In fact, over 80 different IBM products use IBM Cloudscape for many different reasons, including ease of deployment, portability, "hands-free" operation, an open standards-based Java engine, the small footprint, and more. For example, IBM Cloudscape powers products such as WebSphere Application Server, DB2 Content Manager, WebSphere Portal Server, IBM Director, Lotus Workplace, and many others. The IBM Cloudscape engine is a transparent component of all these products, and that is the whole point! Despite its application-transparency, you should be able to sense the power of this database engine because it is trusted to support these enterprise products.
As you probably have figured out by now, IBM has open sourced the IBM Cloudscape technology as Apache Derby and remains solidly committed to its future success. Throughout this book, we will use the term Apache Derby to represent both the IBM Cloudscape and Apache Derby databases because they are identical. There are some add-ons for IBM Cloudscape that you can freely download; where appropriate, we will identify them as such.
Specifically, IBM supports the Apache Derby open source database by:
Contributing the IBM Cloudscape code to serve as the code base for the Apache database
Donating resources to host a central Web-based location for add-on code, educational materials, support, the IBM DB2 Universal JDBC Driver, interfaces for ODBC, PHP, Perl, .NET, and more. The IBM Cloudscape Web site is available on IBM’s developerWorks at: http://www.ibm.com/developerworks/cloudscape.
Funding a dedicated open source project team that includes a complete development group with database development experience. Some members of this team are Apache Derby committers
Providing hardware resources for nightly builds and testing of the open source code lines
Running a full set of software and function verification test cases, and creating a fully functional open source test suite for Apache Derby
Monitoring multiple Apache- and IBM-based forums and mail lists to offer free advice and best practice information to support the Apache Derby community
Why should you be interested in developing on the Apache Derby platform? The Apache Derby platform:
Is easy to deploy. This database requires no installation: just copy a 2 MB .JAR file and set the CLASSPATH environment variable. Because it is Java-based, the database runs anywhere a standard JVM (J2SE 1.3 or higher) can be installed: from Macintosh to mainframe, and all points in between. In addition to this Apache Derby databases (and their data) are platform-independent and can be moved to any machine by simply zipping up your files and emailing them.
Requires no DBA skills or administration effort. When using Apache Derby as an embedded solution, the application automatically starts the relational engine. Upgrades to future versions are done in-place, at connection time. Apache Derby automatically reclaims space, updates statistics, and much more. Quite simply, you do not need to staff your project with a DBA.
To be a player in the open source movement, you must be a proponent of open standards. Arguably, no other large IT company in the world has done more for the open source movement and open standards than IBM. In fact, today IBM backs over 150 different open source projects.
Specifically, Apache Derby uses open standards technology such as the American National Standards Institute’s Structured Query Language (ANSI SQL), JDBC, SQLJ, and more. In fact, because Apache Derby is open source, future plans could include distributing Apache Derby with various mainstream Linux distributions as an accompanying database.
The IBM user community provides valuable feedback to this open source project, including bug reports and feature requests. Although IBM Cloudscape is the same database as the Apache Derby database available to the open source community, the IBM Cloudscape product has a separately purchasable service and support contract, and comes with a graphical-based installation and setup wizard to make full platform deployments (which include binary add-on features from IBM, such as an ODBC interface) easier and more consolidated.
Apache Derby addresses a unique market need and is a great fit for many workloads. Although Apache Derby enriches an environment steeped with a heavy Java investment and an open source middleware stack, it isn’t just for Java developers. APIs are provided (either directly or through a download) for PHP, Perl, CLI, ODBC, and .NET.
In this chapter, we’ll discuss the Apache Derby and IBM Cloudscape platforms, differences between them (again, there is nothing from a code perspective), why IBM is involved, why now, more than ever, you should consider a relational storage engine for your applications if you’re not already using one, and more.
If You’re Not the Kind of Person Who Reads Introduction Chapters ...
We recommend that you read this chapter anyway to get a good level of detail about Apache Derby, the motivation behind what IBM is doing in the open source space (it’s a continuation of previous works actually), why open source in the first place, and more.
If you're not going to read this chapter, but you want a one-minute overview of Apache Derby and IBM Cloudscape, the following paragraphs, courtesy of Kathy Saunders (Release and QA Manager for IBM Cloudscape) and Jean Anderson (Architect for IBM Cloudscape) summarize this product quite well:
"Apache Derby is a lightweight, embeddable relational engine in the form of a Java class library. Its native interface is Java Database Connectivity (JDBC), with Java-relational extensions. It implements the SQL92E standard as well as many SQL 99 extensions. The engine provides transactions and crash recovery, and allows multiple connections and multiple threads to use a connection. Apache Derby can be easily embedded into any Java application program or server framework without compromising the Java-ness of the application because it is a Java class library. Derby's support for complex SQL transactions and JDBC allows your applications to migrate to other SQL databases, such as IBM DB2Universal Database (UDB), when they need to grow.
Apache Derby Network Server provides multi-user connectivity to Apache Derby databases within a single system or over a network. The Apache Derby Network Server receives and replies to queries from clients using the standard Distributed Database Architecture (DRDA) protocol. Databases are accessed through the Apache Derby Network Server using the IBM JDBC driver and the DB2 UDB JDBC universal driver.
There are several technical aspects that differentiate Apache Derby from other database systems:
It's easy to administer. When embedded in a client application, a Derby system requires no administrative intervention.
It's embeddable. Applications can embed the Database Management System (DBMS) engine in the application process, eliminating the need to manage a separate database process or service.
It can run as a separate process, using the Network Server framework or a server framework of your choice.
It is a pure Java class library: This is important to Java developers who are trying to maintain the advantages of Java technology, such as platform independence, ease of configuration, and ease of installation.
It needs no proprietary Java Virtual Machine (JVM). Written entirely in the Java language, it runs with any certified JVM.
The engine is lightweight. It is about 2 MB of class files, and it uses as little as 4 MB of Java heap.
It provides the ability to write stored procedures and functions in Java that can run in any tier of an application. Derby does not have a proprietary stored procedure language; it uses JDBC.
Apache Derby is also like other relational database systems. It has transactions (commit and rollback), supports multiple connections with transactional isolation, and provides crash recovery.
The unique combination of technical capabilities allows application developers to build data-driven applications that are pervasive (run anywhere), deployable (downloadable), manageable, extensible, and connectable."