For more about creating predicates, see Predicate Programming Guide. If the predicate combines textual and nontextual comparisons, it is likely to be more efficient to specify the nontextual predicates first for example, (salary > 5000000) AND (lastName LIKE 'Quincey') is better than (lastName LIKE 'Quincey') AND (salary > 5000000). If a fetch request requires a compound predicate, you can make the fetch more efficient by ensuring that the most restrictive predicate is the first, especially if the predicate involves text matching ( contains, endsWith, like, and matches). How you use predicates can significantly affect the performance of your application. You can also minimize the number of objects you have in memory. Avoid executing multiple requests if you can instead combine them into a single request that will return all the objects you require. In a Cocoa application that leverages Cocoa bindings, given that Cocoa bindings are reliant upon key-value coding and key-value observing, it would be difficult to build a raw data storage mechanism that provides the same level of efficiency as Core Data.Įach round trip to the persistent store (each fetch) incurs an overhead, both in accessing the store and in merging the returned objects into the persistence stack. When you store and retrieve data in a manner that is compliant with key-value coding and key-value observing, it is likely that using NSManagedObject will be faster than any other storage mechanism-including for the simple get/set cases. In particular, it leverages the information about the types of data that is available through introspecting the model. NSManagedObject uses an internal storage mechanism for data that is highly optimized. Implementing and supporting undo and redo in a large application, for example, is usually difficult. At the same time the benefit typically increases. As the complexity of an application increases, the proportionate overhead that Core Data imposes typically decreases. If you implemented this functionality yourself, it is quite likely that the overhead would exceed that imposed by Core Data. However, even a simple Core Data-based application supports undo and redo, validation, and object graph maintenance, and provides the ability to save objects to a persistent store. Overhead versus Functionality in Core Dataįor a very simple application Core Data adds some overhead-compare a plain Cocoa document-based application with a Cocoa Core Data document-based application. When working with large binary objects, review Binary Large Data Objects (BLOBs). Unless your entities themselves have very large attributes or large numbers of properties, 10,000 objects is considered a fairly small size for a data set. The SQLite store can scale to terabyte-sized databases with billions of rows, tables, and columns. Systems.Core Data is a rich and sophisticated object graph management framework capable of dealing with large volumes of data. Runs on all Windows CE versions since WCE 2.10. Version of SQLite optimized to run on Windows CE devices (Handhelds, qrfSQL2 Database Engine - an abstractions.Anubis language has a native supports of SQLite 3.Please indicate SQLite version(s) supported. ![]() ![]() If you know of a driver or wrapper for SQLite that is not listed below, please feel free to add it to the list.
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