I'm coding mmorpg server emulator (hobby project) and i've stopped on writing data access layer. The thing is that i can't use ORM (performance matter). I've read a lot about Repository pattern but it seems like it does not fit well into my project because I'm gonna need methods like: (player db) GetAllByLevel(...), GetByName(...), etc. I want my application to be database agnostic. (I'm using sql server for now but i would like to add support for mysql later) Which data access pattern would fit into my project?
Sorry for my bad english.
One more question. I've read that repository pattern operates on the agreggate root. I've got 3 tables player, player_friend and player_chest. Player is an agreggate root and if i'm not wrong i should create just one repository (PlayerRepository) that could have methods like: GetFriends([player id], ...), GetChest([player id], ...) and so on. Am i right?
I've read a lot about Repository pattern but it seems like it does not fit well into my project because I'm gonna need methods like: (player db) GetAllByLevel(...), GetByName(...), etc.
On the contrary. There are a lot of faulty repository pattern examples out (typically leaky abstractions) which teach you wrong. GetAllByLevel is imho a good method since it describes the role of the method quite clear.
I've written about the repository pattern: http://blog.gauffin.org/2013/01/repository-pattern-done-right/. Do also read the abstraction link in the beginning of the article.
The thing is that i can't use ORM (performance matter).
No problem. The repository pattern is used to abstract away the data source, no matter which kind it is.
If you want to use vanilla ADO.NET you can read this blog post: http://blog.gauffin.org/2013/01/ado-net-the-right-way/
One more question. I've read that repository pattern operates on the agreggate root. I've got 3 tables player, player_friend and player_chest. Player is an agreggate root and if i'm not wrong i should create just one repository (PlayerRepository) that could have methods like: GetFriends([player id], ...), GetChest([player id], ...) and so on. Am i right?
No. I would say that Friends is a root too. Read this article about designing aggregates: http://dddcommunity.org/library/vernon_2011