How to use variables in MongoDB query?

Question

Is it possible to use a variables in MongoDB's query like this?

var FOO="123";
var BOO="323";
user.findOneAndUpdate({_id: userID},{$set:{FOO:BOO}}

BOO - the value, is working fine and it's being assign, while FOO - the key is not.

No, in MongoDB Foo is not a variable but a key "FOO" not FOO — Manjeet Thakur, Jan 07 '18 at 11:28

score 5 · Accepted Answer · answered Jan 07 '18 at 11:41

5

In MongoDB as such no functionality but you can do this in javascript like this

    var FOO="123";
    var BOO="323";
    user.findOneAndUpdate({_id: userID},{$set:{[FOO]:BOO}}

answered Jan 07 '18 at 11:41

Manjeet Thakur

Thanks for your answer, could you explain why this syntax actually works? – Andriy Simonov Jan 07 '18 at 12:05
@AndriySimonov you can read [here](https://stackoverflow.com/questions/2462800/how-do-i-create-a-dynamic-key-to-be-added-to-a-javascript-object-variable) – Manjeet Thakur Jan 07 '18 at 12:16
@ManjeetThakur Thanks - PhpStorm doesn't recognize this syntax...but the code is running .. – RoyBarOn Jan 08 '18 at 07:52
@RoyBarOn Please accept the answer if this is working for you – Manjeet Thakur Jan 08 '18 at 08:35

1 Answers1