I am using prestashop 1.6.1.3 Version. When I checked the ps_product table I have seen a field quantity. I udpdated the value there directly in the database, but to my surprise I didn't see any reflection in the total quantity available in the front-end. After checking this I found the quantity available is coming from the field sav_quantityfield in the ps_stock_available table.
Please tell me for what is this quantity field used?