Don't think this is a realistic option. As you can see we're checking and working with `select`, `condition`, `order`, `group`, `join` and `having` attributes here. Nested arrays within `select` is illogical (can't imagine in what curcumstances it would be possible and i never met such code). As for `condition`, `order`, `group`, `join` and `having`: they're not intended to store array typed values at all.