Android SQLite TutorialSQLite is an open-source relational database i.e. Used to perform database operations on android devices such as storing, manipulating or retrieving persistent data from the database.It is embedded in android bydefault. So, there is no need to perform any database setup or administration task.Here, we are going to see the example of sqlite to store and fetch the data. Data is displayed in the logcat. For displaying data on the spinner or listview, move to the next page.SQLiteOpenHelper class provides the functionality to use the SQLite database. SQLiteOpenHelper classThe android.database.sqlite.SQLiteOpenHelper class is used for database creation and version management.
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Nov 21, 2015 157 Android Studio SQLite OnCreate OnUpgrade Constructor. Cancel Unsubscribe. Subscribe Subscribed. Android studio: Use attach SQLite database file in assets folder with. Feb 23, 2015 This video is part of an online course, Developing Android Apps. Check out the course here: https://www.udacity.com/course/ud853.
For performing any database operation, you have to provide the implementation of onCreate and onUpgrade methods of SQLiteOpenHelper class. Constructors of SQLiteOpenHelper classThere are two constructors of SQLiteOpenHelper class. ConstructorDescriptionSQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version)creates an object for creating, opening and managing the database.SQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version, DatabaseErrorHandler errorHandler)creates an object for creating, opening and managing the database.
It specifies the error handler.Methods of SQLiteOpenHelper classThere are many methods in SQLiteOpenHelper class. Some of them are as follows: MethodDescriptionpublic abstract void onCreate(SQLiteDatabase db)called only once when database is created for the first time.public abstract void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)called when database needs to be upgraded.public synchronized void close closes the database object.public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion)called when database needs to be downgraded.SQLiteDatabase classIt contains methods to be performed on sqlite database such as create, update, delete, select etc. Methods of SQLiteDatabase classThere are many methods in SQLiteDatabase class.
Some of them are as follows: MethodDescriptionvoid execSQL(String sql)executes the sql query not select query.long insert(String table, String nullColumnHack, ContentValues values)inserts a record on the database. The table specifies the table name, nullColumnHack doesn't allow completely null values. If second argument is null, android will store null values if values are empty. The third argument specifies the values to be stored.int update(String table, ContentValues values, String whereClause, String whereArgs)updates a row.Cursor query(String table, String columns, String selection, String selectionArgs, String groupBy, String having, String orderBy)returns a cursor over the resultset.Example of android SQLite databaseLet's see the simple example of android sqlite database.
Hello,I have upgraded my version of SQLCipher from 1.1.0 to 2.0.8, in order to get this to work I require to call upgradeDatabaseFormatFromVersion1To2 on the 1.1.0 DBs. How I have tried to implement this is to increase the DB version and then in the onUpgrade function call the upgradeDatabaseFormatFromVersion1To2 function.The problem I am having is the onUpgrade function is not being called when I create my SQLiteOpenHelper class.
I have check the versions of the DB using getVersion, they are correct. I have also manually called the upgradeDatabaseFormatFromVersion1To2 function on a 1.1 DB and when I import the DB it works fine.Any ideas why the onUpgrade is not firing, I thought of function template changes, or maybe the order in which I am calling these functions. Hello,So in fact the events are firing correctly. What I think is raising the exception is trying to open the DB (with Cipher1.0.1) with the 2.0.8 libararies.
This will happen before trying to call the upgradeDatabaseFormatFromVersion1To2 from the onUpgrade function in the SQLiteOpenHelper class.What I have done is call the getWritableDatabase function if this throws an exception, then I call upgradeDatabaseFormatFromVersion1To2 and call again getWritableDatabase, this works but is not the ideal solution.Is there any way to detect the SQLCipher version on a DB before calling the getReadable/WriteableDatabase? That way I can know more exactly when to call the upgrade procedure.thanks.
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