在 2015年12月31日，上午3:00，Michael Armbrust <firstname.lastname@example.org> 写道：The goal here is to ensure that the non-deterministic value is evaluated only once, so the result won't change for a given row (i.e. when sorting).On Tue, Dec 29, 2015 at 10:57 PM, 汪洋 <email@example.com> wrote:Hi fellas,I am new to spark and I have a newbie question. I am currently reading the source code in spark sql catalyst analyzer. I not quite understand the partial function in PullOutNondeterministric. What does it mean by "pull out”? Why do we have to do the "pulling out”?I would really appreciate it if somebody explain it to me.Thanks.