Configuration storage setup [file vs. database]

Question

I see programmers putting a lot of information into databases that could otherwise be put in a file that holds arrays. Instead of arrays, they'll use many tables of SQL which, I believe, is slower.

CitrusDB has a table in the database called "holiday". This table consists of just one date column called "holiday_date" that holds dates that are holidays. The idea is to let the user add holidays to the table. Citrus and the programmers I work with at my workplace will prefer to put all this information in tables because it is "standard".

I don't see why this would be true unless you are allowing the user, through a user interface, to add holidays. I have a feeling there's something I'm missing.

Answer 1

Sometimes you want to design in a bit of flexibility to a product. What if your product is released in a different country with different holidays? Just tweak the table and everything will work fine. If it's hard coded into the application, or worse, hard coded in many different places through the application, you could be in a world of pain trying to get it to work in the new locale.

By using tables, there is also a single way of accessing this information, which probably makes the program more consistent, and easier to maintain.

Sometimes efficiency/speed is not the only motivation for a design. Maintainability, flexibility, etc are very important factors.

Answer 2

The main advantage I have found of storing 'configuration' in a database, rather than in a property file, or a file full of arrays, is that the database is usually centrally stored, whereas a server may often be split across a farm of several, or even hundreds of servers.

I have implemented, in a corporate environment, such a solution, and the power of being able to change configuration at a single point of access, knowing that it will immediately be propagated to all servers, without the concern of a deployment process is actually very powerful, and one that we have come to rely on quite heavily.

Answer 3

The actual dates of some holidays change every year. The flexibility to update the holidays with a query or with a script makes putting it in the database the easiest way. One could easily implement a script that updates the holidays each year for their country or region when it is stored in the database.