如何插入或更新数据库行的特定字段？

Question

I am using a database table with my android application. What i want to do is insert a row if does not exist else update an entry in it? I am using the following code but found no luck.

public boolean insertIntoOrder(String couponBrand, String couponTitle, String couponDenomination, int couponCount) {
        database = this.getWritableDatabase();
        ContentValues orderContentValues = new ContentValues();
        orderContentValues.put(KEY_ORDER_BRAND, couponBrand);
        orderContentValues.put(KEY_ORDER_TITLE, couponTitle);
        orderContentValues.put(KEY_ORDER_DENOMINATION, couponDenomination);
        orderContentValues.put(KEY_ORDER_COUPON_COUNT, couponCount);
        boolean responseValue = checkOrderConfirmation(couponBrand, couponTitle, couponDenomination);
        if (responseValue == true) {
            database.insert(TABLE_ORDER_CONFIRMATION, null, orderContentValues);
        }
        else {
            couponCount = couponCount++;
            database.execSQL("UPDATE " + TABLE_ORDER_CONFIRMATION + " SET " + KEY_ORDER_COUPON_COUNT + " = ? WHERE " + KEY_ORDER_BRAND + " = ? AND " + KEY_ORDER_TITLE + " = ? AND " + KEY_ORDER_DENOMINATION + " = ?", new String[] {couponCount + "", couponBrand, couponTitle, couponDenomination});
        }
        return true;
    }

public boolean checkOrder(String couponBrand, String couponTitle, String couponDenomination) {
        database = this.getReadableDatabase();
        try {
            checkOrderConfirmationCursor = database.rawQuery("SELECT * FROM " + TABLE_ORDER_CONFIRMATION + " WHERE " + KEY_ORDER_BRAND + " = ? AND " + KEY_ORDER_TITLE + " = ? AND " + KEY_ORDER_DENOMINATION + " = ?", new String[] {couponBrand, couponTitle, couponDenomination});

            if (checkOrderConfirmationCursor == null) {
                if (checkOrderConfirmationCursor.getCount() <= 0) {
                }
            }
            else {
                return true;
            }
        }
        catch (SQLiteException sqle) {
            sqle.printStackTrace();
        }
        return false;
    }

I want to update coupon count if the new row contains duplicate data but doesn't get something to do so. Any help would be appreciable. Thanks in advance.

Answer 1

Try changing checkOrder to:

public boolean checkOrder(String couponBrand, String couponTitle, String couponDenomination) {
    database = this.getReadableDatabase();
    try {
        Cursor checkOrderConfirmationCursor = database.rawQuery("SELECT * FROM " + TABLE_ORDER_CONFIRMATION + " WHERE " + KEY_ORDER_BRAND + " = ? AND " + KEY_ORDER_TITLE + " = ? AND " + KEY_ORDER_DENOMINATION + " = ?", new String[] {couponBrand, couponTitle, couponDenomination});

        if (checkOrderConfirmationCursor != null
                && checkOrderConfirmationCursor.getCount() > 0) {
            return true
        }
    }
    catch (SQLiteException sqle) {
        sqle.printStackTrace();
    }
    return false;
}

Also your main method is calling checkOrderConfirmation but the method is named checkOrder ...