LANSA’s Metadata Repository is more than field definitions, validation rules and reusable components – it promotes an entirely different approach to application development.
More than a data dictionary
Defining data and the business rules for managing the data is an ongoing challenge. Hard coding this information in programs increases the maintenance burden and promotes inconsistency with the rules residing in multiple places. Creating a data dictionary is one way to resolve the problem. The data dictionary places data definitions and associated business rules in one place. However, the information in a data dictionary is static and passive – the data dictionary is only a partial solution.
The application architecture incorporated into the LANSA Metadata Repository extends the role of a data dictionary so that the metadata repository becomes an active participant in the application. The metadata repository is the guardian of the data and provides the data management services layer for the application architecture. The data management services ensures the integrity of data by managing all access to the database. Programs only update the database by placing requests to the data management services.
The metadata repository is both the custodian of the data and business rule definitions and the enforcer of the rules. When rule definition and enforcement is the responsibility of one entity – the metadata repository – ensuring the integrity of the data is easier and maintenance is reduced.
Application portability is now a reality
One reason to implement our metadata repository is so that your business applications become abstracted from the technology layer. You are no longer limited to a particular combination of hardware, operating system, database or user interface technology. Contrast this technology neutral stance with, say, Microsoft .NET applications that only run on Windows servers or large JEE applications that demand powerful enterprise servers. If you are replacing a legacy system because the technology has become outmoded, who’s to say that the next system you implement won’t soon start showing its age? To keep gambling on technology trends is to be certain of ‘losing big’ at least once. Our customers describe LANSA as their insurance against technology change, because it insulates them from the risks associated with being locked into an old technology, platform or operating system. By choosing LANSA they avoid this technology trap and stayed focused on achieving their business outcomes.
Significantly reducing your maintenance burden
Another measurable benefit of our metadata repository is the effect that it has on lowering the maintenance burden throughout the useful life of a system. It’s not uncommon to find LANSA users reporting a 90% reduction in their application maintenance effort and costs. This staggering reduction is the cumulative effect of many design decisions that are built into the LANSA platform.
The benefits of object orientation without the complexity
For instance, a whole library of built-in functions means that LANSA programs are smaller than you would expect. Smaller programs means less code that, obviously, equates to lower maintenance. But even more significant is the amount of reuse that occurs because of the shared repository and the fact that a modification to anything can be made just once and then applied to all affected programs without recompilation. These benefits are not dissimilar to those you would expect from adopting the Object-Oriented programming model with concepts of inheritance, modularity, polymorphism and encapsulation. At LANSA we found a way to deliver on the promise of OO in such a simple way that developers don’t even have to think about the plumbing anymore, they can just focus on getting the job done.