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POAndroid database query not working properly
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copied!<p>I've made a database that has information like this <a href="http://i170.photobucket.com/albums/u244/therealbbri06/database.jpg" rel="nofollow">http://i170.photobucket.com/albums/u244/therealbbri06/database.jpg</a></p> <p>and I'm trying to get the groupName from the database using this</p> <pre><code>public String readNameFromPosition(int position) { Cursor c; c = myDataBase.query("hikingGroups", new String[] { "groupName" }, "position=\'" + position + "\'", null, null, null, null); if (c.moveToFirst()) { return c.getString(0); } else { return "" + c.getCount(); } } </code></pre> <p>When position = 0 the groupName is properly retrieved, but whenever the position is equal to any other valid number c.getCount() returns "0". Any help? I can post more of the code if needed, just ask. Also readNameFromPosition() is inside my DataBaseHelper class.</p> <p>UPDATE: My code</p> <pre><code>package bry.Bicker.OjaiHiking; import java.io.IOException; import android.app.Activity; import android.database.SQLException; import android.graphics.Typeface; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemClickListener; import android.widget.AdapterView.OnItemSelectedListener; import android.widget.Gallery; import android.widget.TextView; import android.widget.Toast; public class OjaiHikingActivity extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); final DataBaseHelper theDb = new DataBaseHelper(getApplicationContext()); try { theDb.createDataBase(); } catch (IOException ioe) { throw new Error("Unable to create database"); } try { theDb.openDataBase(); } catch (SQLException sqle) { throw sqle; } final Gallery hikesGallery = (Gallery) findViewById(R.id.gallery1); hikesGallery.setAdapter(new ImageAdapter(this)); hikesGallery.setOnItemSelectedListener(new OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) { String groupName = ""; int position = hikesGallery.getSelectedItemPosition(); Toast.makeText(getApplicationContext(), "" + position, Toast.LENGTH_SHORT).show(); groupName = theDb.readNameFromPosition(position); TextView tV = (TextView) findViewById(R.id.groupName); Typeface font = Typeface.createFromAsset(getAssets(), "arialbd.ttf"); tV.setTypeface(font); tV.setText(groupName); } @Override public void onNothingSelected(AdapterView<?> arg0) { } }); hikesGallery.setOnItemClickListener(new OnItemClickListener() { public void onItemClick(AdapterView parent, View v, int position, long id) { } }); } } </code></pre> <p>The code for DataBaseHelper.java</p> <pre><code>package bry.Bicker.OjaiHiking; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import android.content.Context; import android.database.Cursor; import android.database.SQLException; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteException; import android.database.sqlite.SQLiteOpenHelper; public class DataBaseHelper extends SQLiteOpenHelper { // The Android's default system path of your application database. private static String DB_PATH = "/data/data/bry.Bicker.OjaiHiking/databases/"; private static String DB_NAME = "Ojaiker.db"; private SQLiteDatabase myDataBase; private final Context myContext; public DataBaseHelper(Context context) { super(context, DB_NAME, null, 1); this.myContext = context; } public void createDataBase() throws IOException { boolean dbExist = checkDataBase(); if (dbExist) { // do nothing - database already exist } else { this.getReadableDatabase(); try { 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); } @Override public synchronized void close() { if (myDataBase != null) myDataBase.close(); super.close(); } public String readNameFromPosition(int position) { Cursor c; c = myDataBase.query("hikingGroups", new String[] { "groupName" }, "position=\'" + position + "\'", null, null, null, null); if (c.moveToFirst()) { return c.getString(0); } else { return "" + c.getCount(); } } @Override public void onCreate(SQLiteDatabase db) { } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } </code></pre>

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