need provision to create funnels to be split by month, day, hour of _time column

[Ramesh Bhana Byndoor]

As of now funnels can be grouped by only commons columns available in table,It's very good and important to have group by month, day, hour for _time column. It's not possible as of now.

[Burak Emre Kabakcı]

Duplicate of rakam-io/rakam-api#71