I created custom field 'A' for sale.order table. field 'A' is defined as String in db. A values are numbers most of the time (eg. 50011) and sometimes default strings(eg. 'default'). I want to get top 10 A field numbers in a query. I wrote:

`recent_orders = request.env['sale.order'].sudo().search(
 [('...')],
limit=10,
order='A desc')`
but it compares A data as strings. How can I make it compare them as integers and ignore string fields.