Migrating an application from Oracle to another DBMS is not adding a feature. I would think you could have also sold the app to other companies running on Oracle. It then just becomes a cost/benefit analysis. Is it worth 100hrs?
How many times has the opposite happened? Someone builds an app to be database agnostic using abstracted database layers, only to never have the system need to run on a different DBMS. I have seen this one 15 times easy as well. The abstraction for the sake of portability also has a performance hit that continues to cost.
I am not trying to argue the specifics as much as to say that when you try to code for future features, there is a pretty high error rate in knowing what those features will be and what they will need. This is especially true for startups that are likely to iterate their business model several times after 1.0.
Using the hotel example as a model, let's say that after launch the company decided that combining discounts wasn't nearly as effective as negotiating special rates with the hotels. They couldn't figure this out until after they launched, but it took them longer to figure it out because they were busy creating a dynamic rules engine instead of selling hotel reservations.
How many times has the opposite happened? Someone builds an app to be database agnostic using abstracted database layers, only to never have the system need to run on a different DBMS. I have seen this one 15 times easy as well. The abstraction for the sake of portability also has a performance hit that continues to cost.
I am not trying to argue the specifics as much as to say that when you try to code for future features, there is a pretty high error rate in knowing what those features will be and what they will need. This is especially true for startups that are likely to iterate their business model several times after 1.0.
Using the hotel example as a model, let's say that after launch the company decided that combining discounts wasn't nearly as effective as negotiating special rates with the hotels. They couldn't figure this out until after they launched, but it took them longer to figure it out because they were busy creating a dynamic rules engine instead of selling hotel reservations.