Setting a field as index: true should also consider creating a compound index on createdAt

[finkinfridom]

We are using the REST APIs to import a lot of data: the more the data, the slower the API.
We started adding index: true (on the properties we used for filtering) but performances didn't change.

Profiling the database we noticed most of the commands coming from the APIs:

• had a find statement with our filter
• had a sort operation on createdAt

the sort operation (I think it's coming from the payload's core code) caused the index to be partially used.

As per the documentation, we accessed payload.db[collectionSlug].schema.index() method to apply our custom indexes:

payload.db.collections[slug].schema.index(
  { [our_filter_field]: 1, createdAt: -1 },
    {
      background: true,
    }
 );

This improved performances at API level and produced benefits on database side.

Shouldn't this approach be part of the payload's core? I mean, adding both the field index and the field+createdAt field index?

Thanks