I have many form in my application I want to store data locally when net is not available.
and if net is available then send to server.
please let me know how to implement this.
Thanks
You can use Core Data, SQLite with FMDB, plist serialisation of just plain and simple NSCoding.
You can use core-data to store the data locally for iPhone.
Introduction to Core Data
SQLite is also good but i`ll prefer core data.
Related
I am going to use Core Data and SQLite together for managing big amount of data on iOS devices. Is that good solution? Are there other ways?
Sqlite can handle very large ammount of data. and core data also use sqlite in backend. SO your approach is right. You should go for this.
for more detail see this:
http://www.sqlite.org/limits.html
There are two ways in which you can write data to file in iOS.
One is NSUserDefaults and the other is Core Data.
NSUserDefaults is not the proper way for storing large amounts of data. It's used to store application settings and temporary data.
Core Data is the proper way for storing and managing large ammounts of data.
I have several big plists in my app. I use them to get necessary input data to my app. While app is running, this data used in various random visual representations. Also, I have favorites feature, where I save some favorite pieces of data. For favorites feature I use CoreData. I transfer some object from my "runtime" data to CoreData and save it.
But should I transfer all data from plists to CoreData, when I launch app for the first time? Or is it ok, to use plists to get data from them every launch?
For example, if we'd talking about reading app. We have some text file on disk. Should I transfer all file to CoreData, when launch first time? Or is it ok, just to save user bookmarks to CoreData?
Core data and plist both are used for store the data. so, if you get data from plist or core data at every launch, there is no problem at all. But if you want to manage complex relational database then you should use core data or sqlite. so, choose storing system as per your requirement like if you want to store user's default credential then you can use nsuserdefault and if you use it to store complex data then also it will work fine but you will possible to face trouble to face some kind of functional operation. So, main concern and your answer there is no difference you get in performance whatever database system you used.
Hoe this will help :)
If you have to only read the data or update all data from plist allmost all the time plist may be ok, also it will be more easy to access then Core Data
Both plist and Core data can be used as persistant storage, but Core Data will have some addtional benifit like i have listed below:
Data stored in the Core Data is pretty secure, so if you can store some sesitive information in the Core Data, data store in plist can be seen directly in some ways.
If you have to perform some insert,update,delete or search on the data it will be better on the Core Data instead of plist.
If you want something like relation or mapping between data it will be possible with Core Data only
So based on the requirement you can choose your storage options
I am new in core data please help me in some confusions...
If core data use sqlite in back end then why we use core data not sqlite??
How it is faster then sqlite.
I read a difference that In core data when we want to edit anything it loads all data in memory..but if it loads then why app. not getting slow or crash.
How to show data of a (.sqlite) file that store in Document Directory.
core data is use for persistence storage but it's not a data base(Explain me)???.
Please define all things to me...
Thanks in advance.
If core data use sqlite in back end then why we use core data not sqlite??
Core data doesn't always use SQLite , SQLite is one type of store option( most widely used ), there are two other types available as well
Check this coredata store types
How it is faster then sqlite.
Core data is not an replacement to SQLite , it is like an ORM for SQLite , it handle all heavy work and provide easier interface to work with SQLite , it handles store connection , querying storing , managing and tracking in memory changes etc
I read a difference that In core data when we want to edit anything it loads all data in memory..but if it loads then why app. not getting slow or crash.
This is wrong , core data does not load everything in memory unless you query it yay ways , in general when you fetch an entity it
returns NSManagedObject instance to work with that entity
How to show data of a (.sqlite) file that store in Document Directory.
What do you mean by show data in SQLite file , u will query what data you want using NSPredicate and get an array of objects as response
The .sqlite database will be stored within app sandbox folder
Check this sqlite storage
core data is use for persistence storage but it's not a data base(Explain me)???.
Coredata is not an persistence storage it's persistence store manager, as I said above it handles all heavy lifting work like creating connection , executing query , converting result to NSManagedObject , tracking object changes , persisting it to SQLite and managing entire object graph you loaded into memory
It's hard to compare core-data with sqlite because these are two different technologies.
However here are few things you won't get from sqlite out of the box.
Built-in change tracking and undo support. Core Data provides built-in management of undo and redo beyond basic text editing.
Easy iCloud storage integration (with NSManagedDocument)
Optional integration with the application’s controller layer to support user interface synchronization.
Eg:- Core Data provides the NSFetchedResultsController object on iOS
Full, automatic, support for key-value coding and key-value observing.
Instead of writing SQL, you can create complex queries by associating an NSPredicate object with a fetch request. NSPredicate provides support for basic functions, correlated subqueries, and other advanced SQL. With Core Data, it also supports proper Unicode, locale-aware searching, sorting, and regular expressions.
Merge policies.
Core Data provides built in version tracking and optimistic locking to support automatic multi-writer conflict resolution.
Core Data can reduce the memory overhead of your program by lazily loading objects. It also supports partially materialized futures, and copy-on-write data sharing.
Core Data is the best option to use but if somehow you want to port the application to android or windows and want to keep the code similar then you can go for SQLITE as SQLite is supported by all major platforms. Whereas core data is only part of iOS. Regarding various doubts you can refer this link
Use Core Data or not?
I'm creating an iOS application that has a Twitter-like feed of data. I'm currently planning on storing the data on Parse. However, what is the most efficient way to store retrieved objects locally for use when there does not exist a network connection? It sounds like using Core Data is overkill since I'm storing the data on Parse anyway. Can the Parse caching system do this for me or is there something else more appropriate? On a similar note, is there a simple way to check if this locally saved data is up-to-date?
I recommend you have a look at SQLite, especially with the FMDB Objective-C wrapper classes.
Parse has the capability to cache objects locally. If your app can tolerate the characteristics of caching, then just use that.
My own app will not, so I am using CoreData as my local store. My app has to be able to operate fully when disconnected from Parse, so I have to have something more than cached data. I looked at FTASync and found the concept very useful. When I got into the code though I realized I needed something much more robust, so I have ended up doing a completely new utility to sync Parse with CoreData. This is a huge job, so don't take it on unless your need is commensurate.
-Bob
There are various ways for iPhone applications to save data (for example: NSUserDefault, XML, document, SQLite, etc.).
Our company always uses NSUserDefault to save data. However, I don't think NSUserDefault is very good because in my experience, it has been slow.
I am curious how you store data for your applications and when you recommend using each of the different methods. Please share your experiences that will help me to understand the advantages and disadvantages of these different storage types and develop a more efficient application for my users.
You can store small data in NSUserDefaults but when you have large database then you need sqlite or coredata for storing the database. use of coredatabase is good for big database this is provided by apple and it is to efficient in accessing database.
NSUserDefaults or document directory is used for small database(suppose need to store user name for single user or some other info).
You just need to know about sql queries to store data in a SQLite3 Database or You can use Core Data for back end storage. Core Data is one of the best options to use for storing data.
NSUserDefault should be used for storing small information.
You can use NSUserDefaults for storing any small data which you want to persist when your application closes. This you can use to store login details but yes if it is be secured, use keychain. You can definely use NSUserDefaults for storing setting options.
SQLite database is any easy way to store large data. Core Data is best option. but you can use SQLite if your application data is not too large.
SQlite Database can also be used to store BLOB data e.g. to store pdf file bytes downloaded from server and whenever you want to use it, just write those bytes to pdf file. This will also keep data security since BLOB data in SQLite cannot be viewed.
Its good to use coreData for large data storage in the IPhone Memory space. ITs a wrapper on top of the database which helps us to store in the form of objects.....
U can find many examples on this...