tree 0e79c43671271ed90262b29e18c99cf065f54bc4
parent 15d47507bf3548f1a03ac967c057c53270d09f57
author Avery Pennarun <apenwarr@gmail.com> 1355466451 -0500
committer Avery Pennarun <apenwarr@gmail.com> 1355466451 -0500

Add count_nz (count nonzero) aggregation function.

Also prevent sum(stuff_including_null) from producing NaN as the answer.