How to fetch data from multiple columns in sqlite android using cursor

Question

I want to fetch data from multiple rows and columns using curser using this below code

  Cursor getallrecords(){

    SQLiteDatabase dbb = this.getReadableDatabase();

    Cursor cursor = null;

    if (dbb != null){
        Log.d("cursor","not null");
      
        cursor = dbb.rawQuery(" SELECT * FROM " + TABLE_NAME,null);

        }else{
        Log.d("cursor","null");
    }

    return cursor;
    }

On logcat it shows the cursor is not empty and returns data. But when I try to set that data which cursor carries on ArrayList using the below code.

  void read(){
    Cursor cursor = save_barcode.getallrecords();

    if (cursor.getCount() != 0){
        cursor.moveToFirst();
        while(cursor.moveToNext()){
            url.add(cursor.getString(1));
            type.add(cursor.getString(2));
            date_and_time.add(cursor.getString(3));
        }
    }

    if (!url.isEmpty()){
        Log.d("message","not null");
    }else {
        Log.d("url","null");
    }

    if (!type.isEmpty()){
        Log.d("message","not null");
    }else {
        Log.d("type","null");
    }
    if (!date_and_time.isEmpty()){
        Log.d("message","not null");
    }else {
        Log.d("date","null");
    }
}

Then in logcat it shows URL,date_and_time, type all of these three are empty. So if anyone knows how to fetch data from multiple rows and column using cursor then help me

Answer 1

The obvious problem with your code is that you are using moveToFirst() and after that moveToNext() , so it is certain that you lose the 1st row.
If all you have in the table is just 1 row then the lists will be empty.
No need to check getCount() , so remove if and no need for moveToFirst() .

Change to this:

void read(){
    Cursor cursor = save_barcode.getallrecords();
    if (cursor == null) return; 
    while (cursor.moveToNext()) {
        url.add(cursor.getString(1));
        type.add(cursor.getString(2));
        date_and_time.add(cursor.getString(3));
    }
    cursor.close();

   ...................
}