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Android SQLite查詢太慢

[英]Android SQLite querys are too slow

大家好 我的應用程序中有一個查詢,該查詢經常被調用,這需要很多時間。 我的數據庫是使用SQLiteCipher加密的(我知道這會降低性能,所以我只調用和打開一次DB)。 所以實際上我有一個帶有自定義適配器的列表視圖,其中列出了模具名稱,lastMassage和lM的時間。 所以我必須做這項工作:

public Massage getLastMassage(String ChatNumber) {
    String[] args = {ChatNumber};
    //String selectQuery="SELECT * FROM " + MassageDBHelper.DATABASE_NAME + " WHERE PhoneNumber=?";
    //Cursor cursor=database.rawQuery(selectQuery,args);
    Cursor cursor = database.query(MassageDBHelper.DATABASE_NAME, columns, "PhoneNumber=?", args, null, null, null);

    cursor.moveToLast();
    Massage massage = cursorToMassage(cursor);
    cursor.close();

    return massage;
}

那是我的databaseHelperClass中稱為MassageDataSource的代碼,我也嘗試過查詢字符串,但是Performance並沒有區別。 在我的CustomAdapter中,我必須為每個聊天(每個被寫的人)執行以下操作:

Massage lastMassage = massageDataSource.getLastMassage(kontaktItem.getNummer());
    Date date = lastMassage.getTimeAsDate();
    cal.setTime(date);
    int Jahr = cal.get(Calendar.YEAR);
    int Monat = cal.get(Calendar.MONTH);
    int Tag = cal.get(Calendar.DAY_OF_MONTH);
    int Stunden = cal.get(Calendar.HOUR_OF_DAY);
    int Minuten = cal.get(Calendar.MINUTE);

    if (Jahr < Kalenderjahr || Monat < Kalendermonat || Tag + 1 < Kalendertag) {
        viewHolder.Uhrzeit.setText(String.format("%02d", Tag) + "." + String.format("%02d", Monat) + "." + Jahr % 1000);
    } else if (Tag < Kalendertag) {
        viewHolder.Uhrzeit.setText(R.string.gestern);
    } else {
        viewHolder.Uhrzeit.setText(String.format("%02d", Stunden) + ":" + String.format("%02d", Minuten));
    }

    viewHolder.Kontaktname.setText(kontaktItem.getName());
    viewHolder.Chatsnippet.setText(lastMassage.getMassageText());
    //set Image from server
    return view;

編輯這里也是cursorToMassage函數,稱為:

private Massage cursorToMassage(Cursor cursor) {
    int idPhoneNumber = cursor.getColumnIndex(MassageDBHelper.COLUMN_PHONENUMBER);
    int idType = cursor.getColumnIndex(MassageDBHelper.COLUMN_TYPE);
    int idMassagetext = cursor.getColumnIndex(MassageDBHelper.COLUMN_MASSAGETEXT);
    int idAttachment = cursor.getColumnIndex(MassageDBHelper.COLUMN_ATTACHMENTID);
    int idTime = cursor.getColumnIndex(MassageDBHelper.COLUMN_TIME);
    int idPosition = cursor.getColumnIndex(MassageDBHelper.COLUMN_POSITION);


    String phoneNumber = cursor.getString(idPhoneNumber);
    String type = cursor.getString(idType);
    String massagetext = cursor.getString(idMassagetext);
    String attachment = cursor.getString(idAttachment);
    String time = cursor.getString(idTime);
    Boolean position = Boolean.valueOf(cursor.getString(idPosition));

    Massage massage;
    if (type.equals("text")) {
        massage = new Massage(position, massagetext, phoneNumber, time);
    } else {
        massage = new Massage(position, attachment, type, phoneNumber, time);
    }

    return massage;
}

嘗試交易。 Android數據庫交易

public Massage getLastMassage(String ChatNumber) {
    database.beginTransaction();
    Massage massage = null;
    try {
        String[] args = {ChatNumber};
        //String selectQuery="SELECT * FROM " + MassageDBHelper.DATABASE_NAME + " WHERE PhoneNumber=?";
        //Cursor cursor=database.rawQuery(selectQuery,args);
        Cursor cursor = database.query(MassageDBHelper.DATABASE_NAME, columns, "PhoneNumber=?", args, null, null, null);

        cursor.moveToLast();
        massage = cursorToMassage(cursor);
        cursor.close();


    } catch {
        //Error in between database transaction 
    } finally {
        database.endTransaction();
        return massage;
    }
}  

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