iPhone应用程序开发中的数据库

Question

I'm creating an app for iPhone, and I want it to load data from an external file (from an URL in a server), to display the hints.

I have read several tutorials, but I don't know yet what is more convenient for me:

• Do I use CoreData?
• Do I create a .sql file and I try to do queries inside the code of my app?
• Do I use a .txt file and try to parse it?
• Do I use a .xml file?

I have to say I'm quite lost at this point, and I really don't know what would be more effective, easy to write (code). And I don't how to access to a file that is in a server and not in the folder of the app itself.

Answer 1

If your loading data from an external server take a look at Rest Kit. It allows you to map an API to objects that are backed by Core Data. http://restkit.org/

Personally I would use CoreData simply because you get a lot of power out of the box right from Core Data, instead of trying to deal with raw sql queries or parsing data.

Another option if your looking for the simplest way to grab a file from a server and map it to an object is to look at .plists for example:

NSDictionary *data = [dict initWithContentsOfURL:[NSURL URLWithString:@"http://server.com/data.plist"]];

Although be careful with that call though because its not asynchronous, and if the file is large and call is made from the Main thread it will block the application.

Answer 2

The best way to implement database on iPhone SDK is to use CORE Data.
- It prevents you to write long sql scripts to fetch & write data in db.
- Easy Implementation.
- Excellent UI to simulate.
- portable
- Can upgrade later if any enhancement required after some time.

So I would like to suggest you to save your data using Core Data. you need to fetch your data from server & call simple methods to save it into App DB using Core data. You even dont need to do much manipulation into it.

Following are some Nice Links for some tutorials:
http://mobile.tutsplus.com/tutorials/iphone/advanced-restkit-development_iphone-sdk/ http://mobile.tutsplus.com/tutorials/iphone/iphone-core-data/