Hi all,
I have a dataframe like following,
+------------------------------------+---------------+
|client_id |timestamp|
+------------------------------------+---------------+
|cd646551-fceb-4166-acbc-b9|1477989416803 |
|3bc61951-0f49-43bf-9848-b2|1477983725292 |
|688acc61-753f-4a33-a034-bc|1479899459947 |
|5ff1eb6c-14ec-4716-9798-00|1479901374026 |
+------------------------------------+---------------+
I want to convert timestamp column into yyyy-MM-dd format.