Develop Reference

Why should I use a ContentProvider with exported=false?

I can't figure out why I should use a ContentProvider with the setting "android:exported=false" in the AndroidManifest.xml. Aren't ContentProviders created to share data between multiple applications? In this way, I am restricting data sharing only to my application and not to external applications. But at this point I can simply use a database in SQLite (maybe with SQLiteOpenHelper).
In the case where I need to create a pre-populated database by loading data from a Rest API, but at the same time I do not need to share my data to other applications, should I create a ContentProvider with the setting "android:exported=false" using the ContentProviderOperation and ContentProviderOperation.Builder Classes (I have seen that these two Classes are used for massive data insertion) ? Or should I create a database in SQLite and insert the data using the INSERT command ?
Thank you!

Entity Framework and Linq equivalent in Android

I am new to Android. I literally just learn Android few days ago. I am just wondering, is there Entity Framework and LINQ equivalent for Android?
Also, I need to store/cache record to a local database. What the best database to use? I am thinking of using SQLite. Is it appropriate for Android?
Thanks!

You need an ORM(Object-Relational Mapper), there is a good cross platform ORM called Realm , Realm gives you a much more programmatic way of accessing and storing data in Objects just like LinQ or EntityFramework and executes queries pragmatically in an object oriented manner.
Sample Realm Code
RealmResults<User> result = realm.where(User.class)
.greaterThan("age", 10) // implicit AND
.beginGroup()
.equalTo("name", "Peter")
.or()
.contains("name", "Jo")
.endGroup()
.findAll();
Documentation

SqLite is appropriate to store local Data for example: if you are retrieving JSON, u can us an sqlite database to store some data for the offline mode, and of course u can use the cache as well, but i recommend u SQLite.
Hope i helped.

ActiveAndroid set instance id

Is it possible to set ID of certain record? I'm importing multi table database into my application database, that is mapped to ActiveAndroid model. I get it over http in json.
It would save a lot of work to preserver those server-side ids on records to have same relations id<>id as on the server.
I planned on deserialisating json to objects using gson and then to save them using activeandroid .save()
Or what is the simplest way to accomplish something like that. Get rid of the the json and do some SQL import?

Not possible. Importing data is to be done by calling SQL inserts directly.

Android-Query(AQuery) is used for SQLite Databse?

I want to fetch data from my sqlite database using AQuery. But I don't have any idea about that. So, Is it possible to fetch data from database using AQuery?? If yes, then How ?

AQuery is not designed for accessing local database. You can try some ORM, like Sprinkles or ORMLite.

How to create database using Db4o in android?

I am developing an App in which now i have to create database for more better user experience. Then i came to know about DB4o which is many times faster tool for creating database than other like SQLite, MySql etc, but the problem is i am not able to find any single example that explains about DB4o and how to create database using Db4o. If anybody has used it, please post an example or send me link.

To store the object in database use
db().store(exercise);
To retrieve All records from database, use
db().query(Object);
To retrieve particular record from database, use
db().queryByExample(Object);
If you need example, Try My blog example using db4o.
In this example, simple student object will be stored in database using db4o. Student object will contain student name, register number, and his age.
Thank you.