How can i arrange the sort order for subcategories from the database. I noticed that catalog_category_entity table has position column. Can i change the order from there ?
absolutley you can, pay attention to the path element, this corresponds to the category id and the 1/64/2467 (example) would correspond to you category tree, with 1 being your root category, just update the position value to see (i have done this quite recently) then do the usual clear caches reindex to reflect on the front end. see below, here the three level 3 categories (id 74,75,76) are ordered so 75 is 1st, 74 is 2nd and 76 is 3rd