Because the various data sets I need are all based on different stipulations.

I need a set of results for WHERE this = 'that' and a second set of results for the exact opposite, WHERE this <> 'that', and of course you cannot combine the two with AND as it would return nothing.

What I meant was on par with doing something like the following (which I know is not possible before anybody tells me):

SELECT this AS first WHERE this = '' this AS second WHERE this <> '' FROM `table`

Therefore I am forced to use

SELECT this AS first FROM `table` WHERE this = ''
SELECT this AS second FROM `table WHERE this <> ''

(these are simplified for the sake of demonstration).