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POSQLite, Tables, Joining
 

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    <p>Android, implementing SQLite</p> <p>These are the tables i have:</p> <p><a href="http://postimg.org/image/jafsx39h7/" rel="nofollow">http://postimg.org/image/jafsx39h7/</a></p> <p>I have the code:</p> <pre><code>public String getWorkoutNameInfo() { // TODO Auto-generated method stub String[] columns = new String[] { KEY_DATE_OF_WORKOUT, KEY_WORKOUT_NAME, KEY_DATE }; Cursor c = ourDatabase.query(TABLE_DATE_WORKOUT, columns, null, null, null, null, null, null); String workoutName2 = ""; int iWorkoutID = c.getColumnIndex(KEY_WORKOUT_NAME); for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()) { workoutName2 = workoutName2 + c.getString(iWorkoutID); } return workoutName2; } </code></pre> <p>This returns workoutName2 which is '2 1 2' </p> <p>Now i need to look up the value for 2 in my WorkoutTable and return 'Back' and produce 'Back,Chest,Back' so i can out put that onto my screen instead of 2 1 2. </p> <p>I understand I'll be using a JOIN statement? However i'm having no luck implementing it.</p> <p>My Table Coding:</p> <pre><code>// WORKOUT TABLE - COLUMN NAMES public static final String KEY_WORKOUT = "workout_id"; public static final String STRING_WORKOUT = "workout_name"; // DATE OF WORKOUT TABLE - COLUMN NAMES public static final String KEY_DATE_OF_WORKOUT = "date_of_workout_id"; public static final String KEY_DATE = "date_of_workout"; public static final String KEY_WORKOUT_NAME = "workout_id"; //TABLE NAMES private static final String TABLE_WORKOUT = "WorkoutTable"; private static final String TABLE_DATE_WORKOUT = "DateofWorkout"; </code></pre> <p>Here is my attempt: </p> <pre><code>public String test(String workoutSelectedNameInfo) { // TODO Auto-generated method stub String NAMEofWorkout = ""; open(); ourDatabase = ourhelper.getReadableDatabase(); Cursor c = ourDatabase .rawQuery( "SELECT * FROM WorkoutTable LEFT JOIN DateofWorkout ON (WorkoutTable.workout_id = DateofWorkout.workout_id) WHERE workout_id = ?", new String[] { "2" }); int iDateofWorkoutsWorkoutId = c.getColumnIndex(KEY_WORKOUT_NAME); for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext()) { NAMEofWorkout = NAMEofWorkout + c.getString(iDateofWorkoutsWorkoutId); } c.close(); ourDatabase.close(); System.out.println(NAMEofWorkout); return NAMEofWorkout; } </code></pre> <p>HOWEVER When it output the 'NameofWorkout' which SHOULD be Chest,Back,Chest i receive nothing at all, absolutely blank. </p>
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