How to modify a spec key in mongoDB

Question posted by David

Hi,

I have programmatically created a lot of fireworks with a certain _category key in their spec.

For some of them I made a mistake an would like to change the value of their _category key in the MongoDB.

I can retrieve their ids using a query:
lpad get_fws -q ‘{“name”: “Water S2: validation”}’ -d ids

How could I modify the spec._category field of this fws ?

Best regards,
David.