We are planning to delete the data present in the table every month. Is there any way to do it automatically each month?
database vendors don't like to take the chance and responsibility for your data in case of a bug's and stuff like this , this is the main reason why you will not see this capability in any of the main databases vendors products .
The answer to your question is :NO ,vertica like other database vendors do not provide such capabilities out of the box , however very you can get it by develop very simple cron script that will drop your the relevent monthly partition each moth .
I hope you will find it useful