get all the ids which do not have transactions in last 6 months : I have a table with three coloumns 
ID DATE desc 
i want to get the ids in a month that have not made transactions in the last 6 months based on the date coloumn.
For instance : an id 123 qualifies for month jan 2018 if it is not having any data in the last 6 months. we need to do this for a span of 2 years from say june 2016 to june 2018.

need help with a sql query for this:
