SQLiteDatabase db = this.getReadableDatabase() Ĭursor cursor = db. String countQuery = "SELECT * FROM " + TABLE_CONTACTS Public class DatabaseHandler extends SQLiteOpenHelper ) Let's see the simple example of android sqlite database. Int update(String table, ContentValues values, String whereClause, String whereArgs)Ĭursor query(String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy) The third argument specifies the values to be stored. If second argument is null, android will store null values if values are empty. The table specifies the table name, nullColumnHack doesn't allow completely null values. Long insert(String table, String nullColumnHack, ContentValues values) There are many methods in SQLiteDatabase class. It contains methods to be performed on sqlite database such as create, update, delete, select etc. Public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion)Ĭalled when database needs to be downgraded. Public abstract void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)Ĭalled when database needs to be upgraded. Public abstract void onCreate(SQLiteDatabase db)Ĭalled only once when database is created for the first time. There are many methods in SQLiteOpenHelper class. SQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version, DatabaseErrorHandler errorHandler)Ĭreates an object for creating, opening and managing the database. SQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version)Ĭreates an object for creating, opening and managing the database. There are two constructors of SQLiteOpenHelper class. For performing any database operation, you have to provide the implementation of onCreate() and onUpgrade() methods of SQLiteOpenHelper class. The class is used for database creation and version management. SQLiteOpenHelper class provides the functionality to use the SQLite database. For displaying data on the spinner or listview, move to the next page. Here, we are going to see the example of sqlite to store and fetch the data. So, there is no need to perform any database setup or administration task. used to perform database operations on android devices such as storing, manipulating or retrieving persistent data from the database. Package import import import import import import import is an open-source relational database i.e. The data stored can be checked on the logcat. In the below example, we are demonstrating the usage of the android SQLite database to store and fetch the data. The values to be stored are specified by the third argument. The null values are stored by android, if the second argument is null and the values are empty. Completely null values are not allowed by the nullColumnHack. The table name is specified by the table. To execute the sql query not select query. Some of the important methods of the SQLiteDatabase class are: Method The SQLiteDatabase class has many methods. The methods like create, update, delete, select, etc, that are performed on the SQLite database are included in the SQLiteDatabase class. To be called when the database needs to be downgraded. Public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) To be called when the database needs to be upgraded. Public abstract void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) To be called when the database is created for the first time. Public abstract void onCreate(SQLiteDatabase db) Some of the important methods of the SQLiteOpenHelper class are: Method The SQLiteOpenHelper class has many methods. To create an object that can create, open and manage the database, and to also specify the error handler. SQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version, DatabaseErrorHandler errorHandler) To create an object that can create, open and manage the database. SQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) This was a simple Android SQLite Database tutorial, in which we learn how to add a Record to Database, Delete a Record and fetch a Record from Database. The SQLiteOpenHelper class has two constructors. The implementation of onCreate() and onUpgrade() methods of SQLiteOpenHelper class is required to be provided to perform any database operation. The functionality to use the SQLite database is provided by the class which is used for database creation and version management.
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