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The differences between Core Data and a Database



DatabaseCore Data
Primary function is storing and fetching dataPrimary function is graph management (although reading and writing to disk is an important supporting feature)
Operates on data stored on disk (or minimally and incrementally loaded)Operates on objects stored in memory (although they can be lazily loaded from disk)
Stores "dumb" dataWorks with fully-fledged objects that self-manage a lot of their behavior and can be subclassed and customized for further behaviors
Can be transactional, thread-safe, multi-userNon-transactional, single threaded, single user (unless you create an entire abstraction around Core Data which provides these things)
Can drop tables and edit data without loading into memoryOnly operates in memory
Perpetually saved to disk (and often crash resilient)Requires a save process
Can be slow to create millions of new rowsCan create millions of new objects in-memory very quickly (although saving these objects will be slow)
Offers data constraints like "unique" keysLeaves data constraints to the business logic side of the program

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