Hi Hive users, We create a table with sql which contains the dense_rank function,and then run count distinct on this table, we found that with diffrent dense_rank parameters or even defferent columns,we will get the defferent count distinct results: 1.Less data will be ok(in our test case,200 million rows will get the same results,but 300 million rows will get the different results ) 2.Different dense_rank parameters may be get the different results ,e.g "dense_rank() over(distribute by a,b sort by c desc)" and "dense_rank() over(distribute by a sort by c desc)" 3.All window functions(rank,row_number,dense_rank) have this problem 4.Less column number may be ok 5.Count(1) is ok,but Count distinct gets different results 6.It seems that some rows have been lost and some rows repeated
test data(File is too large to upload.): http://pan.baidu.com/s/1hqnCzze test sql: http://pan.baidu.com/s/1eQna8q2 本电子邮件可能为保密文件。如果阁下非电子邮件所指定之收件人，谨请立即通知本人。敬请阁下不要使用、保存、复印、打印、散布本电子邮件及其内容，或将其用于其他任何目的或向任何人披露。谢谢您的合作！ This communication is intended only for the addressee(s) and may contain information that is privileged and confidential. You are hereby notified that, if you are not an intended recipient listed above, or an authorized employee or agent of an addressee of this communication responsible for delivering e-mail messages to an intended recipient, any dissemination, distribution or reproduction of this communication (including any attachments hereto) is strictly prohibited. If you have received this communication in error, please notify us immediately by a reply e-mail addressed to the sender and permanently delete the original e-mail communication and any attachments from all storage devices without making or otherwise retaining a copy.
