How to create field index for collection?

Hey there,

We are still on version 0.90 of Cockpit CMS, if its relevant. We have a Collection of “Units” that have a field “Serial”. It is important that “Serial” be unique and not duplicated. It doesn’t look like I’m seeing a way to create an index on that field. Is there a built in Cockpit CMS way to do it in the admin dashboard? I’m guessing it’ll have to do with JSON OPTIONS?

We are using MongoDB, so my alternative question is there anything wrong with creating the index directly in the mongo shell?

For example:
db.units.createIndex( { “Serial”: 1 }, { unique: true } )