Rollup in Plyql

Folks I have a requirement of doing rollup in druid using plyql.

I found below link which have a option but no example given.

https://github.com/implydata/plyql/blob/master/README.md

and then tried below query.

bin/plyql -h 13.91.58.243:8082 --rollup -q ‘SELECT entity,product,SUM(MTD_TRANSACTION_SUM), SUM(YTD_TRANSACTION_SUM),SUM(COUNT) FROM transactions WHERE period = “2016-02-17” group by entity,product’

o/p is attached but it is not at all rolled up.

Am I using the correct syntax? can you give any example?

Thanks,

Biplab