javascript - What is need of specifying ref here in the below mongoose schema? What if we don't specify it?

Question

 eventsAttended: [{ type: Schema.Types.ObjectId, ref: 'Event' }]

question from:https://stackoverflow.com/questions/66066964/what-is-need-of-specifying-ref-here-in-the-below-mongoose-schema-what-if-we-don

Answer 1

Ref is an option of mongoose to populate a field given a schema. So in case you omit ref in your "eventsAttended" field, you get only an objectID value, with no reference to any schema.

Docs here: https://mongoosejs.com/docs/api.html#schematype_SchemaType-ref

Guide here: https://mongoosejs.com/docs/populate.html