how to save a result from a mongodb query into a javascript variable?

Question

there are some questions here regarding how to save a result from a query into a javascript varialbe, but I'm just not able to implement them. The point is that I have a much difficult query, so this question is, in my opinion, unique.

Here is the problem. I have a collection namend "drives" and a key named "driveDate". I need to save 1 variable with the smallest date, and other with the biggest date.

The query for the smallest date is:

> db.drives.find({},{"_id":0,"driveDate":1}).sort({"driveDate":1}).limit(1)

The result is:

{ "driveDate" : ISODate("2012-01-11T17:24:12.676Z") }

how dan I save this to a variable, can I do something like:

tmp = db.drives.find({},{"_id":0,"driveDate":1}).sort({"driveDate":1}).limit(1)

Thanks!!!

Answer 1

Assuming you're trying to do this in the shell:

 tmp = db.drives.find({}, {_id:0, driveDate:1}).sort({driveDate:1}).limit(1).toArray()[0]

find returns a cursor that you need to iterate over to retrieve the actual documents. Calling toArray on the cursor converts it to an array of docs.

Answer 2

After some time figuring out, I got the solution. here it is, for future reference:

var cursor = db.drives.find({},{"_id":1}).sort({"driveDate":1}).limit(1)

Then I can get the document from the cursor like this

var myDate = cursor.next()

That's it. Thanks for your help