Well i just want this thing to be clear to me. Were introduced by the OOP approach and the XP Approach. Now i'll give an example that we made for. We are making a large database system and we need to use the XP and OOP approach. So our team head decided that all procedure, connections string, querys must done in a different classes. One for connection string, one for querys, and so on. With that by just calling their methods it would be easier to debug and add new features.

At instance if i have the query method in the query class to be able to execute the query all i just to do is call the connectionstring in the other class and this query method in query class can be now executable. And all this query will be just call in the Application.

Is this good or recommendable and can be understand easier ?

Or its better that the connectionstring and query can be combined together in one class with that it could be a lesser time and lesser space for coding ?