Re: [mongodb-user] How to get last insert id per collection

[Scott Hernandez]

What are you trying to do? Is this to implement some kind of
counter/id-generator?

You can use the special $natural index to get the last document in the
collection; this may not be the latest inserted if an update occurs
where the doc needs to be moved.

On Thu, Feb 3, 2011 at 1:06 PM, behrang <behrang....@gmail.com> wrote:
> Hi,
>
> What is the efficient way to get the last insert _id per collection?
> Something similar to LAST_INSERT_ID in mySQL.
> I am using pymongo 1.9.
>
> Thanks
> Behrang
>
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[behrang]

[behrang]

Thanks for the quick reply.
In our application, client can ask for the last X records. So as you
mentioned, I sort by _id:
db.<mycollection>.find(fields = {"_id"}).sort("_id", -1).limit(X)

Thanks again
Behrang