Manual DAL & BLL vs. ORM

Question

Which approach is better: 1) to use a third-party ORM system or 2) manually write DAL and BLL code to work wi

Answer 1

I have used Bold for Delphi four years now. It is great but it is not available anymore for sale and it lacks some features like databinding. ECO the successor has all that. No I'm not selling ECO-licenses or something but I just think it is a pity that so few people realize what MDD (Model Driven Development) can do. Ability to solve more complex problems in less time and fewer bugs. This is very hard to measure but I have heard something like 5-10 more efficient development. And as I work with it every day I know this is true.

Maybe some traditional developer that is centered around data and SQL say:

1. "But what about performance?"
2. "I may loose control of what SQL is run!"

Well...

1. If you want to load 10000 instances of a table as fast as possible it may be better to use stored procedures, but most application don't do this. Both Bold and ECO use simple SQL queries to load data. Performance is highly dependent of the number of queries to the database to load a certain amount of data. Developer can help by saying this data belong to each other. Load them as effiecent as possible.

2. The actual queries that is executed can of course be logged to catch any performance problems. And if you really want to use your hyper optimized SQL query this is no problem as long as it don't update the database.

There is many ORM system to choose from, specially if you use dot.net. But honestly it is very very hard to do a good ORM framework. It should be concentrated around the model. If the model change, it should be an easy task to change database and the code dependent of the model. This make it easy to maintain. The cost for making small but many changes is very low. Many developers do the mistake to center around the database and adapt everthing around that. In my opinion this is not the best way to work.

More should try ECO. It is free to use an unlimited time as long the model is no more than 12 classes. You can do a lot with 12 classes!