Best way to store and retrieve thousands of places on iOS

My situation: I have an app that needs to store 10,000 - 30,000 locations in some sort of storage method, which are then displayed on a MKMapView as individual pins. I also have a server that needs to be able to add to 开发者_如何学Pythonthe database through pushing out changes.

Through grouping pins I've eliminated all issues with the MKMapView, my biggest focus is now on speed, storage and being able to add and replace the storage contents. What I'm currently doing is I have a text file of currently 1,000 locations as JSON-formatted, then they're just read as an array and sent to my custom map view (no issues there). My only issue is how I could update that text file (rather than downloading massive amounts of data), and store almost 30,000 locations.

Is this even feasible? It seems my current setup could scale pretty much perfectly, it's just this updating system that is causing me a headache.

Your current setup won't scale forever because you have to load the entire file into memory in one chunk. Eventually it will get to large to manage and will eat up to much memory. Unable to purge memory in the event of system low-memory, the system will shut your app down i.e. it won't be able to stay in the background but will have to reboot each time the user switches back to it.

To update, you will have to load in the entire file, parse the JSON, figure out how to update the resulting data structure, then write it all to file. One error anywhere in the process could corrupt the entire file.

You really need to look at using Core Data or even SQL. Core Data has a learning curve but once you master it, it makes implementing designs like your app trivial. You also get automatic scaling and efficient memory management.