How to get all keys + in a collection + mongodb +mongoose

Question

I want to get all distinct keys from a collections in mongoDB. I refereed the following links:

Querying for a list of all distinct fields in MongoDB collection and etc.

But still i didn't get the right solution...

As i am using mongoose in the first link reference syas runCommand is not a function.

As findOne() will give the first document keys alone but i need all distnct keys

userModel.findOne(condition, projection, callback)

Please share your ideas..

Keys means your declared `Model` in mongoose ? I mean let's say you have a model named Book which is `{_id,book_name,publisher}` etc, Do you want them? — Osman Goni Nahid, Aug 01 '18 at 06:40
@Anthony Winzlet Its not a particular filed. I have to get the all the keys in all documents.. — Subburaj, Aug 01 '18 at 07:53
Try the answer here https://stackoverflow.com/a/43570730/2683814 — s7vr, Aug 01 '18 at 10:20

Tushar Nikam · Answer 1 · 2018-08-01T06:24:37.537

0

If you are using Mongoose 3.x, then you can try this :

userModel.find().distinct('_id', function(error, ids) {
    // ids is an array of all ObjectIds
});

Or you can find all the documents and extract key from that like :

var keys = {};
var docKeys = [];
userModel.find({}, function(err, allDocs){
    allDocs.forEach(function(doc){
        docKeys = Object.keys(doc);
        docKeys.forEach(function(docKey){
               if(!keys[docKey]) keys[docKey] = true;
        })
    })     
})

I have just written for getting logic, you can change according to your requirements and efficiency

edited Aug 01 '18 at 06:24

answered Aug 01 '18 at 06:04

Tushar Nikam

594
4
13

Its giving array of `_ids` but i need `keys` – Subburaj Aug 01 '18 at 06:10
I have updated the code, please check if it solves your problem. – Tushar Nikam Aug 01 '18 at 06:25
i already implemented your 2 thought. But what about performance?? Consider if it has some 1 lakh resords?? – Subburaj Aug 01 '18 at 06:33
you can use schema and put restriction on document keys. so you will be sure that document will contain only those keys, and you can get the schema keys using : UserModel.schema.paths – Tushar Nikam Aug 01 '18 at 06:39
Thats i cant restrict.. User can upload any datas – Subburaj Aug 01 '18 at 06:40

score 0 · Answer 2 · answered Aug 01 '18 at 06:48

0

Try like this you will get all of your keys defined into your mongoose model/Schema.

import Model from 'your_model_path'

for(let property in Model.schema.obj){
  console.log("key=====>",property);
}

answered Aug 01 '18 at 06:48

Osman Goni Nahid

1,193
2
15
24

My schema is not fixed, user can upload any data, so ew cant predict the keys – Subburaj Aug 01 '18 at 07:10
then you have to do lengthy things the different doc can be different, merging docs and finding keys too costly. – Osman Goni Nahid Aug 01 '18 at 07:15
.Yes Any optimized solutioon for this?? – Subburaj Aug 01 '18 at 07:21

How to get all keys + in a collection + mongodb +mongoose

2 Answers2