How to merge two columns (containing date&time) for a specific time interval?

Hi, I have two df: df1 and df2. Each of them contain a column named "start" containing date&time dd:mm:yyyy hh:mm:ss. Here an example: start26/06/2015 08:42:0327/06/2015 09:21:3027/06/2015...

02 February 2016 3,590 1 View