How to use a variable as a field name in mongodb-native findOne()?

Question

I have this data in mongodb:

{       "name": "Amey",     "country": "India",     "region": "Dhule,Maharashtra" } 

and I want to retrieve the data while passing a field name as a variable in query.

Following does not work:

var name = req.params.name; var value = req.params.value; collection.findOne({name: value}, function(err, item) {     res.send(item); }); 

How can I query mongodb keeping both field name and its value dynamic?

Answer 1

You need to set the key of the query object dynamically:

var name = req.params.name; var value = req.params.value; var query = {}; query[name] = value; collection.findOne(query, function (err, item) { ... }); 

When you do {name: value}, the key is the string 'name' and not the value of the variable name.

Answer 2

Just put the variable in []

var name=req.params.name; var value = req.params.value; collection.findOne({[name]:value}, function(err, item) { res.send(item); });