[SOLVED] Should I use ObjectID or uid(implemented by myself) to identify user?

Should I use ObjectID or uid(implemented by myself) to identify user?

I am new to mongodb and database. Implement a function to make uid and use the local ObjectId. Which is better?

Solution

You should leave ObjectID generation to the clients/drivers. This makes sure that generated IDs are unique among many things, such as time, server and process. Using the standard ObjectID also means that methods implemented by drivers (such as getTimestamp()) work.

However, if you are thinking of using your own type of ID for the _id field (ie, not the standard ObjectID type), then that makes a viable choice. For example, if you want to store information about a twitter user, then using the user's twitter ID as _id value makes perfect sense. Personally, I try to rely on the ObjectID type as little as I have to, as often collections will have a field in each document already that uniquely identifies each document.