Hive - Group by datetime column to date only

Question

In my table eventtime column looks like,

2017-03-25T03:18:00001Z
2017-03-25T05:21:00013Z

I want to group by eventtime with date only.

Like

2017-03-18, 2017-03-21

Answer 1

GROUP BY CAST(myDateTime AS DATE)

Answer 2

Use it both in the GROUP BY and the SELECT clauses.

cast (from_iso8601_timestamp(eventtime) as date)