MongoDB ID - how to implement sequential custom IDs?

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Problem

Using Mongoose.

  • Mongo automatically creates an _id for each new document in a collection
  • I am creating a user system where i want to implement a simple, sequential id
  • Meaning the first user will be 1, the second 2, etc
  • This is working OK in development, I use the id to work with my user data throughout the app
  • I set a simple variable in my Node application that increases by one every time a user is saved
  • HOWEVER, when the server re-starts, the variable resets to the original value, this is a problem

Solution?

  • At this point in development it is not a big deal, but in the long term, my system is not going to hold up in production
  • I am a newb but I would imagine my Node server will not run uninterrupted forever

Are there any easy solutions to implement what I want?

  • I was thinking maybe i could save a separate document on my DB that contains my counter variable, and find it and increment it and save it again every time i save a user… this doesn’t seem like the most efficient thing in the world
  • my other idea is just to use the mongo _id to do all my lookups
  • idk i find the super long strings annoying and it would be nice to just see user id’s in a simple numerical order

Maybe someone with more db experience can chime in with their thoughts on my situation and ideas. Thanks.

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When all else fails, read the documentation for creating sequential IDs.

Out of curiosity, why do you care if the id is 1,2, or 3 or a randomly created ID? Are you trying to use the id as a way of knowing the order in which the ids were created? If so, they use a date/time field for that.

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good point. i read over the docs and determined i don’t need seq id’s in this case.

i have a created on value in my schema that generates Date.now when a user document is created.

i’m not sure why i cared to be honest. when i started this whole thing i went through this tutorial that was creating id’s in sequence and using those values as part of the routing. so for example, they would have a multiple channels and each channel would be found at /channel/:id and obviously, the integers in sequence look better than the long default _id. since, i am not setting up my routes like that, i guess i don’t even need the sequential ids.

man, i newb out sometimes, there is so much to learn. thanks for responding.

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Those “annoying super long strings” are called ObjectIds and have some unique properties:

  • they include the creation timestamp of the document, which you can retrieve with getTimestamp
  • sorting by _id will (roughly*) sort by the creation time of the documents
  • ObjectIds are unique within your database, and likely unique in the universe
  • they’re fast to generate…
  • …and don’t require a round-trip to the database, which you correctly figured out would be necessary for your solution (“save a separate document on my DB that contains my counter variable”)

* orangematter.solarwinds .com/2019/12/22/what-is-mongodbs-id-field-and-how-to-use-it/

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