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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