Checkboxes in RecyclerView is unchecked when scrolled

Suppose I check an item's checkbox, that also updates the ischecked column in the database with the respective item's id. Then I scroll down and go back to the top, then the top most item's checkbox is automatically unchecked and database is also updated. Even suppose I check two items on the top, when I scroll down the two bottom most items' checkboxes are also checked automatically. How can I resolve this problem in recyclerView?

// costume adapter class
public class DataBeanAdapter extends RecyclerView.Adapter<DataBeanAdapter.ViewHolder> implements View.OnCreateContextMenuListener {
    public List<dataBean> items;
    public int itemLayout;

    @Override
    public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo contextMenuInfo) {
        menu.setHeaderTitle("Select The Action");
        menu.add(0, v.getId(), 0, "Call");//groupId, itemId, order, title
        menu.add(0, v.getId(), 0, "SMS");
    }

    public DataBeanAdapter(List<dataBean> items, int itemLayout) {
        this.items = items;
        this.itemLayout = itemLayout;
    }

    @Override
    public DataBeanAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(itemLayout, parent, false);
        return new ViewHolder(v);
    }

    @Override
    public void onBindViewHolder(final ViewHolder holder, final int position) {
        // On loading the activity recyclerview, setting properties to each list items

        // fetch id with the given item postition
        Cursor cc = myDB.getCursorByPosition(position);
        String idd = cc.getString(cc.getColumnIndex("_id"));


        String taskval = myDB.getTaskValue(idd);

        dataBean item = items.get(position); // trash
        holder.tasks.setText(taskval.trim());

        String iscGet = myDB.getischecked(idd); // false by default

        if (items.get(position).getChecked() == true) {
            holder.isc.setChecked(true);
            items.get(position).setChecked(true);
        } else if (items.get(position).getChecked() == false) {
            holder.isc.setChecked(false);
            items.get(position).setChecked(false);
        } else {
            //leave
        }


        // set inflated checkbox to null
        //   holder.isc.setOnCheckedChangeListener(null);
        //  holder.isc.setChecked(myAdapter.items.contains(items.get(position)));

        holder.isc.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
                Boolean ischecked = items.get(position).getChecked();
                if (ischecked == false) {
                    Cursor cx = myDB.getCursorByPosition(position);
                    String idx = cx.getString(cx.getColumnIndex("_id"));
                    myDB.updateCheck(idx);
                    items.get(position).setChecked(true);

                } else {
                    Cursor cx = myDB.getCursorByPosition(position);
                    String idx = cx.getString(cx.getColumnIndex("_id"));
                    myDB.updateunCheck(idx);
                    items.get(position).setChecked(false);
                }
            }
        });


        holder.tasks.setOnCreateContextMenuListener(MainActivity.this);
        holder.more.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                Cursor c = myDB.getCursorByPosition(position);
                String id = c.getString(c.getColumnIndex("_id"));

                Intent intent = new Intent(MainActivity.this, edit.class);
                intent.putExtra("taskpos", Integer.toString(position));
                intent.putExtra("taskid", id);
                startActivity(intent);

            }
        });
    }

    @Override
    public int getItemCount() {
        return items.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        public TextView tasks;
        public CheckBox isc;
        public ImageView more;

        public ViewHolder(View itemView) {
            super(itemView);
            tasks = (TextView) itemView.findViewById(R.id.taskline);
            isc = (CheckBox) itemView.findViewById(R.id.cbox);
            more = (ImageView) itemView.findViewById(R.id.more);
            // https://developer.android.com/reference/android/support/v7/widget/RecyclerView.ViewHolder.html#isRecyclable()
            //  this.setIsRecyclable(false); /// prevents checkbox misbehaving


        }

    }
}

public List<dataBean> getAllData() {
    List<dataBean> list = new ArrayList<>();
    Cursor cursor = myDB.SelectData();


    while (cursor.moveToNext()) {

        int tasks = cursor.getColumnIndex("tasklist");
        int ischecked = cursor.getColumnIndex("ischecked");
        String tasksv = cursor.getString(tasks);
        String ic = cursor.getString(ischecked);
        dataBean bean = new dataBean(tasksv, Boolean.parseBoolean(ic));
        list.add(bean);

    }

    return list;
}