# How to find in mongodb

**URL:** <https://discourse.nodered.org/t/how-to-find-in-mongodb/25504>\
**Category:** General\
**Created:** [25 April 2020 21:45 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504 "2020-04-25T21:45:08Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![d0d04m3](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/d0d04m3/32/19965_2.png) [@d0d04m3](https://discourse.nodered.org/u/d0d04m3)\
**Post date:** [25 April 2020 21:45 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504/1 "2020-04-25T21:45:08Z")

</div>

hi how find in mongodb data base  
exp I need find this UUID : "a506e376-b38b-473d-a7aa-a70652cdacb5"  
or this id: next and equal :  
how it  
 ![Untitled](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/5/8/58c6e0f948deb44290bd0c5aa37e79adb7808da4.png)  
I use this msg but not work

```auto
msg.find = {"UUID":{ $in:"a506e376-b38b-473d-a7aa-a70652cdacb5"}};
return msg;

```

but return all document

![Untitled](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/f/7/f7e5ef0260c159057497606f43d3c3510a3d0c00.png)

---

<div class="post-metadata">

**Author:** ![knolleary](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/knolleary/32/3_2.png) [@knolleary](https://discourse.nodered.org/u/knolleary)\
**Post date:** [25 April 2020 22:08 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504/2 "2020-04-25T22:08:48Z")

</div>

Which mongo node are you using?

Does its sidebar help say to put the query in `msg.find`? Off the top of my head, I'm not aware of a node that uses msg.find (but I haven't tried them all). Most nodes would expect the query to be in msg.topic or msg.payload.

---

<div class="post-metadata">

**Author:** ![d0d04m3](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/d0d04m3/32/19965_2.png) [@d0d04m3](https://discourse.nodered.org/u/d0d04m3)\
**Post date:** [25 April 2020 22:35 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504/3 "2020-04-25T22:35:04Z")

</div>

> [@knolleary](#):
>
> Which mongo node are you using?

> **[node-red-node-mongodb](https://flows.nodered.org/node/node-red-node-mongodb)**
>
> Node-RED nodes to talk to a Mongo database

---

<div class="post-metadata">

**Author:** ![d0d04m3](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/d0d04m3/32/19965_2.png) [@d0d04m3](https://discourse.nodered.org/u/d0d04m3)\
**Post date:** [25 April 2020 22:51 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504/4 "2020-04-25T22:51:20Z")

</div>

```auto
msg.projection = {"UUID":{ $in:"a506e376-b38b-473d-a7aa-a70652cdacb5"}, "ack":1};
return msg;

```

error return

```auto
"MongoError: Unsupported projection option: UUID: { $in: "a506e376-b38b-473d-a7aa-a70652cdacb5" }"

```

---

<div class="post-metadata">

**Author:** ![knolleary](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/knolleary/32/3_2.png) [@knolleary](https://discourse.nodered.org/u/knolleary)\
**Post date:** [25 April 2020 22:54 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504/5 "2020-04-25T22:54:21Z")

</div>

That node expects the find options to be in msg.payload.

---

<div class="post-metadata">

**Author:** ![d0d04m3](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/d0d04m3/32/19965_2.png) [@d0d04m3](https://discourse.nodered.org/u/d0d04m3)\
**Post date:** [25 April 2020 23:17 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504/6 "2020-04-25T23:17:04Z")

</div>

so I use this

```auto
msg.payload = {_id: {$gt: ObjectId("5ea4995f4a677c4e68acb899" )}}

```

now error return:

```auto
"ReferenceError: ObjectId is not defined (line 4, col 27)"

```

when used this

```auto
msg.payload = {UUID: {$in:"a506e376-b38b-473d-a7aa-a70652cdacb5" }}

```

return error

```auto
"MongoError: $in needs an array"

```

if used without $in

```auto
msg.payload = {"UUID":"a506e376-b38b-473d-a7aa-a70652cdacb5"}

```

```auto
{
"_msgid":"42d8881b.1fdbc8",
"topic":"",
"payload":[
{
"_id":"5ea4995f4a677c4e68acb89a",
"topic":"ps30kv/RTU",
"payload":"[{\"topic\":\"ACK-RTU\",\"payload\":\"switch dp\"}]",
"qos":0,
"retain":false,
"_msgid":"e45548ec.cfe208",
"time":"Sat Apr 25 2020 21:11:11 GMT+0100 (GMT+01:00)",
"ack":true,
"UUID":"a506e376-b38b-473d-a7aa-a70652cdacb5"
}
]
}

```

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [24 June 2020 23:18 UTC](https://discourse.nodered.org/t/how-to-find-in-mongodb/25504/7 "2020-06-24T23:18:09Z")

</div>

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.