Using $lookup on collectionname including underscore

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1

I need to do a $lookup against a collection that have starts with a number and has underscore (_) in the name.

using the below is not working. what is best practies when doing this lookup?

from: 12collection_name

2

Hi @Eirik_Andersen

What version shell/driver and mongodb are you using?

This works for me in mongosh

s0 [primary] test> db.foo.aggregate({$lookup:{from: "61thing_foo", localField: 'b', foreignField:'_id',as: 'x'}})
[
  {
    _id: ObjectId("6472b1eb000b5a7208da81ba"),
    a: 'one',
    b: 1,
    x: [ { _id: 1, t: 'some words' } ]
  }
]
3

Hi Chris,
Sorry, forgot to mention the version. We are running on MongoDB 4.4.

4

In

it looks like you are not putting the name within quotes. In most programming languages, this means you are using a variable. In most programming languages, variables cannot start with numbers. I would try with

from: "12collection_name"

as shown in Chris’ example.

5

Hi steevej,

Already tried that, and it doesn’t help.

6

Hi @Eirik_Andersen
did you also try single quotes? ’ instead of " ?
Can’t imagine that this really solves it, just to not miss this point out.
The exact error, your code, env setup might be helpful to share.

7

Show the code you are using and share any error/warning message you are getting.

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