Changing Default timestamp format in Shiny

[Bob Tao]

When a data frame made from a query to a table in PostgreSQL database is rendered through renderDataTable, the timestamp column is displayed as:

2016-09-29T14:38:03Z

and it can be changed to after Sys.setenv(TZ='CDT') :

2016-09-29T09:38:03Z

I have a couple of questions.

1. Is this a good practice (could it cause other problems)?

2. Is there an option we could use to set the display to other format, for example,'20160929093803'?

Thanks,