![]() ![]() Queries can be created via the rawQuery()and query()methods or via the SQLiteQueryBuilderclass. ContentValuescan be used for inserts and updates of database entries. The keyrepresents the table column identifier and the valuerepresents the content for the table record in this column. The object ContentValuesallows to define key/values. In addition it provides the execSQL()method, which allows to execute an SQL statement directly. More specifically SQLiteDatabaseprovides the insert(), update()and delete()methods. This way your implementation of SQLiteOpenHelperstays readable, even if you have several tables.īase class for working with a SQLite database in Android and provides methods to open, query, update and close the database. These methods are called in the corresponding methods of SQLiteOpenHelper. This class defines static onCreate()and onUpgrade()methods. Tip It is good practice to create a separate class per table. Several Android functions rely on this standard. The database tables should use the identifier _idfor the primary key of the table. The SQLiteOpenHelperclass provides the getReadableDatabase()and getWriteableDatabase() methods to get access to an SQLiteDatabaseobject either in read or write mode. Both methods receive an SQLiteDatabaseobject as parameter which is the Java representation of the database. This methodĪllows you to update an existing database schema or to drop the existing database and recreate it via the onCreate()method. If the database version is increased in your application code. The framework, if the database is accessed but not yet created. onCreate()- is called by onUpgrade()- called, In this class you need to override the following methods to create and update your database. In the constructor of your subclass you call the super()method of SQLiteOpenHelper, specifying theĭatabase name and the current database version. Creating and updating database with SQLiteOpenHelper To create and upgrade a database in your Android application you create a subclass of the SQLiteOpenHelperclass. Packages The android.databasepackage contains all necessary classes for working with databases. Please check the Android development tutorial to learn the basics.ģ. Prerequisites for this tutorial The following assumes that you have already basic knowledge in Android development. FILENAMEis the name you specify in your application code for the database.Ģ. DATAis the path which the Environment.getDataDirectory()method returns. The parts of the above directory are constructed based on the following rules. If your application creates a database, this database is by default saved in the directory DATA/data/APP_NAME/databases/FILENAME. Therefore it is recommended to perform database operations asynchronously. Afterwards the database is automatically managed for you by the Android platform.Īccess to an SQLite database involves accessing the file system. You only have to define the SQL statements for creating and updating the database. Using an SQLite database in Android does not require a setup procedure or administration of the database. SQLite in Android SQLite is embedded into every Android device. ![]() More information about SQLite can be found on the SQLite website. you can write an integer into a string column and vice versa. SQLite itself does not validate if the types written to the columns are actually of the defined type, e.g. All other types must be converted into one of these fields before getting saved in the database. SQLite supports the data types TEXT(similar to String in Java), INTEGER(similar to long in Java) and REAL (similar to double in Java). 250 KByte) which makes it a good candidate from being embedded into other runtimes. The database requires limited memory at runtime (approx. ![]() SQLite supports standard relational database features like SQL syntax, transactions and prepared statements. What is SQLite? SQLite is an Open Source database. Storage location of the SQLite database 10.2. Accessing SQLite databases directly 10.1. Tutorial: SQLite, own ContentProvider and Loader 9.1. What is a content provider?Īndroid SQLite database and content provider - Tutorial 5.2. ListViews, ListActivities and SimpleCursorAdapter 4. Creating and updating database with SQLiteOpenHelper 3.3. The tutorial is based on Eclipse 4.2, Java 1.6 and Android 4.2. It also demonstrates the usage of the Loader framework which allows to load data asynchronously. It also demonstrates how to use existing ContentProvider and how to define new ones. Using the Android SQLite Database This tutorial describes how to use the SQLite database in Android applications. Version 4.9 Copyright © 2010, 2011, 2012, 2013 Lars Vogel Revision History Revision 0.1 Android SQLite database and content provider - TutorialĪndroid SQLite database and content provider Tutorial Based on Android 4.3 ![]()
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