HyperGraphDB at Strange Loop 2010

I will be giving a brief talk on HyperGraphDB on the Strange Loop conference in St-Louis on October 14. The talk will focus on the HyperGraphDB data model, architecture and why it's well suitable for complex software systems, as opposed to other models, SQL, NOSQL, or conventional graph databases.

This conference is highly recommended! Judging by the program and the list of speakers, it is truly as the organizers promote it: from developers for developers. It is about cutting edge technology, it is about everything hot going on this days in the world of software development, it is technical and it looks fun. So, please come buy!

Website: http://strangeloop2010.com/

You are encouraged to register with the website, and interact with the speakers online before the conference.

Cheers,
Boris

HyperGraphDB at IWGD 2010

The architecture of HyperGraphDB will be presented at The First International Workshop on Graph Database during WAIM 2010 (the Web Age Information Management conference) taking place on July 15-17 in Jiuzhai Valley, China. For more information, please see:

http://www.icst.pku.edu.cn/IWGD2010/index.html

The presentation will be done by Borislav Iordanov and it will focus on the unique HyperGraphDB data model, type system and discuss some of the architectural choices and their impact on performance. The accompanying paper can be found here:

http://kobrix.com/documents/hypergraphdb.pdf

HyperGraphDB 1.1 Alpha Released

Kobrix Software is pleased to announce the release HyperGraphDB 1.1 Alpha. HyperGraphDB is a general purpose, extensible, portable, distributed, embeddable, open-source data storage mechanism. Designed specifically for artificial intelligence and semantic web projects, it can also be used as an embedded object-oriented database for projects of all sizes.

This is an initial, alpha release of the next version of HyperGraphDB. A complete list of changes is availabe at:

http://code.google.com/p/hypergraphdb/wiki/NextReleaseNotes

To download, please vist the HyperGraphDB project home page at Google.

For more information about HyperGraphDB's features, documentation and additional pointers, please visist the HyperGraphDB home page at Kobrix.

Poetry About Our Art

About 14 years ago, at the pick of the object-oriented programming craze I came across a publication called On the Origin of Objects, randomly placed amidst the stream of software/OO engineering books at a very reliable computer science bookstore. Surely, I thought, this would get to the bottom of things, somebody has dissected the notion of objects and outlined all the fundamentals I would need to be a successful programmer without the need to skim through endless pages describing ridiculous design processes, trivial principles, inapplicable rules of thumb and what not. It turned out the book had nothing to do with object-oriented programming.

On the Origin of Objects (amazon link) is about metaphysics with computation as the starting point. The author is one of the deepest and most original thinkers I've come across - Brian Cantwell Smith (wikipedia link). Needless to say, I couldn't read it at the time, I wasn't ready for it. That came about 7 years later and it was a memorable, mentally reinvigorating experience. Smith writes beautifully and dances around his insights with such grace and depth. He writes about the kind of computation we do day to day, the real stuff, and he puts common conceptual problems we programmers face into the center stage of philosophy in a way that gives our work those extra dimensions that scientists seem to have always enjoyed - a fundamental, very real connection to the physical world, including, at an even deeper level, a connection with us intentional beings, a set of problems that arise naturally from the practice of our profession, yet quickly reach the most difficult metaphysics in a way that no other practice does.

There are a few (not many) articles you could find on the internet from Prof. Smith, all of them worth reading. However, the purpose of this blurb is to bring to the attention to whoever comes across it his latest work. For the past years, I've been eagerly monitoring and waiting the publication of Age of Significance, which is supposed to be in 7 volumes. The book website, http://ageofsignificance.org/, hadn't changed until just two months ago where it was announced that individual chapters will be published monthly. So far, only the introduction has been posted at http://ageofsignificance.org/aos/en/toc.html and I believe that an attentive read would make my seeming infatuation with this work understandable. Originally, I intended to write a summary of that introduction, highlighting the main points, most of which I'm already familiar with from previous writings (Smith's and others), but I wouldn't want to butcher it. It is philosophy at its best. And it is about the foundation of computing, that which we (should, to say the least) care about. I will just quote the conclusion for the hardcore philosophy skeptics:

Throughout the whole project, I have received countless communications from programmers and computer scientists - over coffee, in the midst of debugging sessions, in conferences, at bars and via email - hoping that it might be possible to say what they feel they know, the absence of which, in some cases, has led to almost existential frustration.

That is pretty much how I've felt more often than not as a programmer. And that is why, to me Smith's work is pure poetry, as philosophy used to be seen at the time of Plato anyway.

Cheers,

Boris

Seco 0.3 Released

Kobrix Software is pleased to announce the release of Seco 0.3 Seco, formerly known as Scriba, is a scripting development environment for JVM-based dynamic languages. Seco has been in active development and use for the past several years and it is a perfect companion to the serious Java developer.

Key features include:

- Support of many popular JVM languages with syntax highlighting and code completion for most.
- Advanced script editing interface based on structured notebooks as popularized by the Mathematica system.
- A WYSIWYG HTML editor for documentation.
- An infinite, zoomable 2D canvas for arbitrary layout of components, container nesting and more.
- Full workspace automatically persisted in an embedded HyperGraphDB database.
- Support for importing 3d party libraries in multiple evaluation contexts.
- Based on the JSR 223 standard for language interoperability - all languages share the same runtime context.
- Real-time collaboration and exchange of components and notebooks via a P2P network.

Seco is perfect not only for prototyping, testing and experimentation, but it is also the ideal tool for learning a given JVM language or a new Java library. It can be used to build complete interactive applications embedded within the environment itself similarly to a life system like Squeak!

Seco is free, open-source, LGPL licensed software.

To download and for more information, please visit the Seco home page at Kobrix.

HyperGraphDB @ NoSQL Live

NoSQL has picked up a lot of steam lately. HyperGraphDB being a NoSQL DB par excellence, we will be joining the upcomping conference organized by the 10gen, the maker of MongoDB:

"NoSQL Live from Boston is a full-day interactive conference that brings together the thinking in this space. Picking up where other NoSQL events have left off, NoSQL Live goes beyond understanding the basics of these databases to how they are used in production systems. It features panel discussions on use cases, lightning talks, networking session, and a NoSQL Lab where attendees can get a practical view of programming with NoSQL databases."

The conference takes place on March 11, 2010. For more information and to register (fees are really small!), goto http://www.10gen.com/events.

Borislav Iordanov will be on the graph databases panel as well as on the live hacking session later in the afternoon. The talk will focus on real world graph database applications and reveal some of the interesting architectural bits behind HyperGraphDB. More extensive chats and demos during the live session.

For more information on HyperGraphDB, visit http://www.kobrix.com/hgdb.jsp

Is HyperGraphDB an Object-Oriented Database?

Back in the 90s, the "killer" of RDBMs were presumed to be the ODBMs. Today it is NoSQL. Why are RDBMs a prey to be killed, and why should any other approach be a voracious predator rather than a gentle companion has never been clear to me. Industry fads are always a bit ridiculous in retrospective, but fortunately the technical advances that fuel them at the beginning often follow their independent paths eventually contributing their fair share to our beloved profession. Strangely, OO databases are now being categorized as NoSQL. So the old and new predators join forces in a cooperative onslaught. Why not? Whatever it takes to get the crowd's attention. Since HyperGraphDB was announced as a graph database, it fits the NoSQL bill, that's good for promotion. But we've received "criticism" in the past that it was actually more of an OO database than a graph database, so why not call it that simply?

Well, for starters objects in memory form a graph, so at a certain abstraction level we are talking about essentially the same thing. But more interestingly, does HyperGraphDB fit the accepted definition of what constitutes an objent-oriented database. According to the ODMBS.ORG:

"An object database management system (ODBMS, also referred to as object-oriented database management system or OODBMS), is a database management system (DBMS) that supports the modelling and creation of data as objects. This includes some kind of support for classes of objects and the inheritance of class properties and methods by subclasses and their objects."

The Object-Oriented Database System Manifesto from 1995 is still the main reference for the core features of an OO database. So let's examine (admittedly, a bit crudely) that paper's defining list and see how it applies to HyperGraphDB:

1. Complex Objects built from simpler ones by applying constructors to them. HyperGraphDB has that - type constructors are fundamental to representing complex values.
2. Object Identity an object has an existence which is independent of its value. This means one can change the value while preserving the identity. The authors note " that identity-based models are the norm in imperative programming languages: each object manipulated in a program has an identity and can be updated. This identity either comes from the name of a variable or from a physical location in memory. But the concept is quite new in pure relational systems, where relations are value-based." HyperGraphDB has identity at its very basis: the atom handle is like a memory location in a universal addressing space. Atom identity in HyperGraph is in fact more fundamental than anything else.
3. Encapsulation, which in a database context is taken to mean "that an object encapsulates both program and data". This is supported via Java. When storing Java objects, the current implementation does not store the program part (the bytecode of a class' methods) because there's no really a need for it. Naturally, this wouldn't be hard to achieve with a different set of type constructors that do store the program. In fact, this is something that we plan to do with Seco.
   
4. Types and Classes - the system should offer some form of data structuring mechanism, be it classes or types. Thus the classical notion of database schema will be replaced by that of a set of classes or a set of types. The distinction between types & classes comes into play mostly at the Java level (HyperGraphDB's "host language" at the moment). Nevertheless, HyperGraphDB's types cover both the notion of a class as a factory of objects with a well-defined extent and of a type as a semantic notion obeying certain composition rules. The core notion of substitutability is expressed with HGSubsumes links. More extensive checking and enforcement is something left for actual type & type constructor implementations.
   
5. Class or Type Hierarchies with various forms of inheritance being distinguished by the authors - substitution, inclusion, constraint and specialisation. HyperGraphDB has a type hierarchy with multiple inheritance via multiple HGSubsumes links between types, but it doesn't make such fine-grained distinctions between the different kinds. Such distinctions are left open to the application. When mapping Java classes to HyperGraphDB types, the HGSubsumes link created between a class and its parent corresponds to "specialisation inheritance". A HGSubsumes link between a class and an implemented interface may correspond to any/all of the other kinds.
6. Overriding, overloading and late-binding are notions at the programming language level that usually apply to operations rather than data and as such are supported only to the extent that HyperGraphDB is being used from an OO language (Java). At the data level, we note that an object property is always fully stored, regardless of its declared type. For instance, if a bean has a property of declared type A, but the actual value is of a subclass B, B will be used as the stored type instead of A. So overriding is supported. In addition, HyperGraphDB supports properties with the same name but different types within a single record: one could have a property "x" of type int and a property "x" of type String within the same complex type. So, overloading is supported as well!
   
7. Computation Completeness is required, but the authors "are not advocating here that designers of object-oriented database systems design new programming languages: computational completeness can be introduced through a reasonable connection to existing programming languages"... which HyperGraphDB does, again via the JVM.
8. Extensibility is required in the following sense: there is a means to define new types and there is no distinction in usage between system defined and user defined types. HyperGraphDB's type system is open and extensible from the very high-level type-constructor-constructors...down to the primitive types which could be replaced as well. So this requirement is met with applause.
9. Persistence should be orthogonal, i.e., each object, independent of its type, is allowed to become persistent as such (i.e., without explicit translation). It should also be implicit: the user should not have to explicitly move or copy data to make it persistent. Yep, check-mark, we've got it.
10. Secondary storage management with "clear independence between the logical and the physical level of the system". Check-mark here too.
11. Concurrency - yes.
12. Recovery - yes, thanks to the very reliable BerkeleyDB.
13. Ad Hoc Query Facility which lets you express non-trivial queries concisely, is efficient and it's application independent. HyperGraphDB meets that requirement, but not with flying colors at this point. More mature DBs have better querying capabilities and we hope to get there soon.

In conclusion, HyperGraphDB is a full-fledged OO database according to the most official definition.

Cheers,
Boris

PS: Perhaps the most prominent OO database in the Java world these days is db4o. I haven't used it, but skimming through tutorials and docs, I don't see what it can do that HyperGraphDB can't. Their querying options might be better (the native queries are quite an advanced concept), and the optimizer might be more advanced, but besides that I challenge readers to tell us what HGDB is missing as a competitor in the object-oriented database space?