![]() databases Code language: SQL (Structured Query Language) ( sql ) database command to display all databases in the current database connection. sqlite> attach database 'c:\sqlite\db\contacts.db' as contacts Code language: JavaScript ( javascript )įourth, use the. Then, use the ATTACH DATABASE statement to create a new database named contacts and associates it in the current database connection. seq name file -Ġ main c:\ sqlite\ db\ chinook. databases command to list all databases in the current database connection. SQLite ATTACH DATABASE exampleįirst, connect to the chinook sample database using sqlite3 command as follows: > sqlite3 c:\ sqlite\ db\ chinook. Note that SQLite automatically deletes all temporary and memory databases when the database connection is closed. If you specify an empty file name '', the statement creates a temporary file-backed database. You can attach multiple in-memory databases at the same time with a condition that each memory database must be unique. In case you want to create a new memory database and attach it to the current database connection, you use :memory: filename. For example, to refer to the people table in the contacts database, you use the contacts.people. Once the additional database attached, you can refer to all objects in the database under the name database_name. If the database file file_name does not exist, the statement creates a new database file. The statement associates the database file file_name with the current database connection under the logical database name database_name. To attach an additional database to the current database connection, you use the ATTACH DATABASE statement as follows: ATTACH DATABASE file_name AS database_name Code language: SQL (Structured Query Language) ( sql ) Therefore, every SQLite database connection has the main database and also temp database in case you deal with temporary database objects. In addition, you can access the temporary database that holds temporary tables and other database objects via the temp database. When you connect to a database, its name is main regardless of the database file name. Introduction to the SQLite ATTACH DATABASE statement Import 7.app.Summary: in this tutorial, you will learn how to attach additional databases to the current database connection using the SQLite ATTACH DATABASE statement. SQLiteDatabase db = this.getReadableDatabase() Ĭursor cursor = db.rawQuery(countQuery, null) 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. SQLite is an open-source relational database i.e. ![]()
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