Setting field2=field1 in MongoDB

Question

I am unable to update my document when I run db.xx.updateOne({_id: ObjectId(""}, {$set: {lq: uq}) I get the error uncaught exception: ReferenceError: uq is not defined

uq field exists and contains integers, not sure why it don't work. Please help.

score 1 · Accepted Answer · answered Feb 07 '22 at 05:08

1

db.collection.update({
  "_id": ObjectId("5a934e000102030405000000")
},
[
  {
    "$set": {
      "field1": "$field2"
    }
  }
])

mongoplayground

answered Feb 07 '22 at 05:08

YuTing

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It didn't work. It set the value for 'lq' to '$uq' not actual uq value – Lucilfer Feb 07 '22 at 05:17
you need `[` & `]` – YuTing Feb 07 '22 at 05:18

Setting field2=field1 in MongoDB

1 Answers1