I need to sort entries numerically on a specific field (which might include text strings) and force all the entries with a text (not integer) appearing in that field to the end of the result set.
i.e. with a data set like:
na, 789, 123, 456
I would want the sort by on channel:entries to return:
123, 456, 789, na
I'm thinking this is completely impossible without some kind of extension but... :?