Getting the Login id

Users I entering my web site by the Member Login button. I want to use the login id (e-mail address) to get the right and only information for the specific user from a collection having the e-mail address as the unique key. What is the field’s name for the userid?

Hi Shimon,
The _id field is always unique, you can use it as the userId field.

I’ll try. Thank you Ido.