OO Programming and Relational Databases

Database application architecture: How does a computer operate?

As I have stated earlier, it depends on how you define the OO-programming application arcitecture: SQL statements should NOT be allowed in the application, but should rather be placed in stored procedures and functions, contained in database packages.

But how do you do that?

Although I deal with data analysis and database modeling, I have to have a certain knowledge on the matter, and I often participate in writing the actual database-side PL/SQL code. So I put up a page on how you define and use a ref cursor as mentioned above.

This worked well and a lot of people were happy. However, a lot of you have wondered how you actually could use that 'miracle' feature.

OK: Back to writing again.

I had to supply you with some info on that. So here is the Java side (application) of how to separate database access from the application logic.

This is very rudimentary, but should give you the picture. I have not taken into account all object-technology terms like encapsulation (but the function obviously is, just look at it again...), methods (overloaded function interface), object instance dynamics (which it supports) and so on.

This is just a simple example on how easy it really is to save the database from inexperienced OO-programming programmers.

Do you get the benefits?

1. The programmer does not need to worry about the database structure
2. Tuning of SQL is done independently of how many times (or rather places) this access path is in use.
3. Changes in the database structure/access paths are not influencing the application logic.
4. Not to mention: It will easily outperform any world-leading (or wannabe) Java programmer.

Actually, I claim that this is a far better approach than the attempts made to create an Object-relational database (whatever that would be), doing trivial mappings, not getting the point that your information structure is not dependent on how you represent it inside a given program in a given programming language.

Well, now I got carried away with programming :-)

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