Ich bin in meinen letzten Phasen der Erstellung einer Datenbank für meine Android-App, aber ich kann nicht scheinen, meine Primärschlüssel zu erhöhen. Hier ist mein Code, wo ich es einrichten,Android SQLite - Primärschlüssel - Einfügen in Tabelle
public class DatabaseHandler extends SQLiteOpenHelper {
// All Static variables
// Database Version
private static final int DATABASE_VERSION = 17;
// Database Name
private static final String DATABASE_NAME = "journeyManager";
// Contacts table name
public static final String TABLE_JOURNEY = "journey";
// Contacts Table Columns names
private static final String KEY_P = "key";
private static final String KEY_ID = "id";
private static final String KEY_DIST = "distance";
private static final String KEY_MPG = "mpg";
private static final String KEY_COST = "cost";
public DatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
// Creating Tables
@Override
public void onCreate(SQLiteDatabase db) {
String CREATE_JOURNEY_TABLE = "CREATE TABLE " + TABLE_JOURNEY + "("
+ KEY_P + " INTEGER PRIMARY KEY," + KEY_ID + " TEXT," + KEY_DIST + " TEXT,"
+ KEY_MPG + " TEXT," + KEY_COST + " TEXT)";
db.execSQL(CREATE_JOURNEY_TABLE);
}
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_JOURNEY);
// Create tables again
onCreate(db);
}
/**
* All CRUD(Create, Read, Update, Delete) Operations
*/
// Adding new contact
void addJourneyData(Journey journey) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_P, journey.getpKey());
values.put(KEY_ID, journey.getId());
values.put(KEY_DIST, journey.getDistance()); // Contact Name
values.put(KEY_MPG, journey.getMpg()); // Contact Phone
values.put(KEY_COST, journey.getCost()); // Contact Phone
// Inserting Row
db.insert(TABLE_JOURNEY, null, values);
db.close(); // Closing database connection
}
// Getting single contact
Journey getJourney(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_JOURNEY, new String[] { KEY_P + KEY_ID +
KEY_DIST, KEY_MPG, KEY_COST }, KEY_P + "=?",
new String[] { String.valueOf(id) }, null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
Journey journey = new Journey();
journey.setPkey(Integer.parseInt(cursor.getString(0)));
journey.setId(String.valueOf(cursor.getString(1)));
journey.setMpg(String.valueOf(cursor.getString(2)));
journey.setDistance(String.valueOf(cursor.getString(3)));
journey.setCost(String.valueOf(cursor.getString(4)));
// return contact
return journey;
}
// Getting All Contacts
public List<Journey> getAllJourneys() {
List<Journey> journeyList = new ArrayList<Journey>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_JOURNEY;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Journey journey = new Journey();
journey.setPkey(Integer.parseInt(cursor.getString(0)));
journey.setId(String.valueOf(cursor.getString(1)));
journey.setMpg(String.valueOf(cursor.getString(2)));
journey.setDistance(String.valueOf(cursor.getString(3)));
journey.setCost(String.valueOf(cursor.getString(4)));
// Adding contact to list
journeyList.add(journey);
} while (cursor.moveToNext());
}
// return contact list
return journeyList;
}
}
Hier ist, wo ich die Details in eine Datenbank von einer Taste auf eine andere Aktivität hinzufügen,
db.addJourneyData(new Journey(1,timeStamp, distanceLabel, mpgAnswer, pplAnswer));
ich an den Punkt gelangen, wo wird es füge den ersten ein, aber von da an wird es sagen, dass der Primärschlüssel nicht eindeutig ist - daher wird die Datenbank nicht aktualisiert.
Auch ich möchte die Daten in absteigender Reihenfolge, um dies zu tun, verwende ich DESC, aber wo soll ich das platzieren?
Jede Hilfe dankbar,
Vielen Dank,