How to do a search in MongoDB as a result of a search?

Question

MongoDB

Is it possible to do a MongoDB lookup as the result of another lookup?
Something like this:
db.table.find({...}).find({...})

Answer 1

Answer 2

You can use aggregation framework
db.col.aggregation({$match:{}},{$match:{}})
will be exactly what you need

Answer 3

I'm afraid to ask: why do you need it? It is possible to unite in one find ().
In general, the find() method returns a cursor object. Methods available on this object: docs.mongodb.org/manual/reference/method/js-cursor
As you can see, the find() method is not among them. So the answer is - You can't do that.

Answer 4

A simple abstract example: we have a database of a million records. And there is a big loop:

for x in range(1 000):
    db.table.find({...}) // При каждой итерации делаем выборку из миллиона записей

But it is possible to pre-filter this million records before the cycle. Thus, a base of 100 records will be obtained, according to which it will be easier to do further searches in a cycle.