add_id just ensures data is a data.table and adds a columns named .id
Usage
add_id(data)
Arguments
data
Source data (data.frame or data.table)
Value
data.table object with a column named .id
Details
add_id in called behing the scence by crazyfy
if needed to ensure a valid id is present in source data.
Still, we recommand to start from a dataset already having an id, be it generated
by a call to add_id or already pre-existing to ensure correct source data enrichment.