choose randomly
If you are going to draw a lottery now, you need to select a lucky user. It can be implemented using the aggregate Aggregate.sample(size: number), then the calling method of sample is as follows:
db.collection('users') .aggregate() .sample({ size: 1 }) .end()The record corresponding to a randomly selected user is returned, and the result is as follows:
{ "_id": "696529e4-7e82-4e7f-812e-5144714edff6", "name": "b" }
to sum up
If you are going to draw a lottery now, you need to select a lucky user. Then using the cloud-developed aggregation method sample, you can easily implement such a scenario.