Question

我正在使用我的android应用程序的数据库表。我想要做的是插入一行，如果不存在，否则更新其中的条目？我使用以下代码，但没有找到运气。

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;
    }

我想更新优惠券数量，如果新行包含重复数据但是没有这样做的话。任何帮助都会很明显。提前谢谢。

Answer 1

尝试将checkOrder更改为：

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;
}

此外，您的主要方法是调用checkOrderConfirmation，但该方法名为checkOrder ...

如何插入或更新数据库行的特定字段？

1 个答案: