SQLite For Android Source Codes
public class SQLiteHelper extends SQLiteOpenHelper { private static final String DATABASE_NAME = "my_database.db"; // TOGGLE THIS NUMBER FOR UPDATING TABLES AND DATABASE private static final int DATABASE_VERSION = 1; // NAME OF TABLE YOU WISH TO CREATE public static final String TABLE_NAME = "my_table"; // SOME SAMPLE FIELDS public static final String UID = "_id"; public static final String NAME = "name"; SQLiteHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL("CREATE TABLE " + TABLE_NAME + " (" + UID + " INTEGER PRIMARY KEY AUTOINCREMENT," + NAME + " VARCHAR(255));"); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w("LOG_TAG", "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); // KILL PREVIOUS TABLE IF UPGRADED db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME); // CREATE NEW INSTANCE OF TABLE onCreate(db); } }
Implementing the database helper class.
public class SQLiteExample extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // INIT OUR SQLITE HELPER SQLiteHelper sqh = new SQLiteHelper(this); // RETRIEVE A READABLE AND WRITEABLE DATABASE SQLiteDatabase sqdb = sqh.getWritableDatabase(); // METHOD #1: INSERT USING CONTENTVALUE CLASS ContentValues cv = new ContentValues(); cv.put(SQLiteHelper.NAME, "jason wei"); // CALL INSERT METHOD sqdb.insert(SQLiteHelper.TABLE_NAME, SQLiteHelper.NAME, cv); // METHOD #2: INSERT USING SQL QUERY String insertQuery = "INSERT INTO " + SQLiteHelper.TABLE_NAME + " (" + SQLiteHelper.NAME + ") VALUES ('jwei')"; sqdb.execSQL(insertQuery); // METHOD #1: QUERY USING WRAPPER METHOD Cursor c = sqdb.query(SQLiteHelper.TABLE_NAME, new String[] { SQLiteHelper.UID, SQLiteHelper.NAME }, null, null, null, null, null); while (c.moveToNext()) { // GET COLUMN INDICES + VALUES OF THOSE COLUMNS int id = c.getInt(c.getColumnIndex(SQLiteHelper.UID)); String name = c.getString(c.getColumnIndex(SQLiteHelper.NAME)); Log.i("LOG_TAG", "ROW " + id + " HAS NAME " + name); } c.close(); // METHOD #2: QUERY USING SQL SELECT QUERY String query = "SELECT " + SQLiteHelper.UID + ", " + SQLiteHelper.NAME + " FROM " + SQLiteHelper.TABLE_NAME; Cursor c2 = sqdb.rawQuery(query, null); while (c2.moveToNext()) { int id = c2.getInt(c2.getColumnIndex(SQLiteHelper.UID)); String name = c2.getString(c2.getColumnIndex(SQLiteHelper.NAME)); Log.i("LOG_TAG", "ROW " + id + " HAS NAME " + name); } c2.close(); // CLOSE DATABASE CONNECTIONS sqdb.close(); sqh.close(); } }
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