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POandroid - read database from local file
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copied!<p>I read and practice via article <a href="http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/" rel="nofollow">http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/</a></p> <p>Here is my sample <a href="http://www.mediafire.com/?f8qbmummo0qeqnv" rel="nofollow">http://www.mediafire.com/?f8qbmummo0qeqnv</a></p> <p>Some body can check and let me know why city table not found ? thanks</p> <p>i have created a database with table </p> <pre><code>city : _id ; name 1 ; abc 2 ; def </code></pre> <p>and in DataNaseHelper.openDataBase i try</p> <pre><code>Cursor result = myDataBase.rawQuery("SELECT * FROM city", null); Log.d("trung", result.getExtras().toString()); </code></pre> <p>But i get error</p> <pre><code>11-25 22:24:13.393: E/AndroidRuntime(337): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.joomavatar.phonebook/com.joomavatar.phonebook.NumberSearch}: android.database.sqlite.SQLiteException: no such table: city: , while compiling: SELECT * FROM city </code></pre> <p>what is wrong here ?</p> <pre><code> public class DataBaseHelper extends SQLiteOpenHelper{ //The Android's default system path of your application database. private static final String DB_PATH = "/data/data/com.joomavatar.phonebook/databases/"; private static final String DB_NAME = "hanoi"; private SQLiteDatabase myDataBase; private final Context myContext; /** * Constructor * Takes and keeps a reference of the passed context in order to access to the application assets and resources. * @param context */ public DataBaseHelper(Context context) { super(context, DB_NAME, null, 1); this.myContext = context; } /** * Creates a empty database on the system and rewrites it with your own database. * */ public void createDataBase() throws IOException{ boolean dbExist = checkDataBase(); if(dbExist){ //do nothing - database already exist }else{ //By calling this method and empty database will be created into the default system path //of your application so we are gonna be able to overwrite that database with our database. this.getReadableDatabase(); try { Log.d("trung", "create table"); copyDataBase(); } catch (IOException e) { throw new Error("Error copying database"); } } } /** * Check if the database already exist to avoid re-copying the file each time you open the application. * @return true if it exists, false if it doesn't */ private boolean checkDataBase(){ SQLiteDatabase checkDB = null; try{ String myPath = DB_PATH + DB_NAME; checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY); }catch(SQLiteException e){ //database does't exist yet. } if(checkDB != null){ checkDB.close(); } return checkDB != null ? true : false; } /** * Copies your database from your local assets-folder to the just created empty database in the * system folder, from where it can be accessed and handled. * This is done by transfering bytestream. * */ private void copyDataBase() throws IOException{ //Open your local db as the input stream InputStream myInput = myContext.getAssets().open(DB_NAME); // Path to the just created empty db String outFileName = DB_PATH + DB_NAME; //Open the empty db as the output stream OutputStream myOutput = new FileOutputStream(outFileName); //transfer bytes from the inputfile to the outputfile byte[] buffer = new byte[1024]; int length; while ((length = myInput.read(buffer))>0){ myOutput.write(buffer, 0, length); } //Close the streams myOutput.flush(); myOutput.close(); myInput.close(); } public void openDataBase() throws SQLException{ //Open the database String myPath = DB_PATH + DB_NAME; myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY); Cursor result = myDataBase.rawQuery("SELECT * FROM city", null); Log.d("trung", result.getExtras().toString()); } @Override public synchronized void close() { if(myDataBase != null) myDataBase.close(); super.close(); } @Override public void onCreate(SQLiteDatabase db) { } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } // Add your public helper methods to access and get content from the database. // You could return cursors by doing "return myDataBase.query(....)" so it'd be easy // to you to create adapters for your views. } </code></pre>

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