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mongodbauto-incrementuniqueidentifierbitsetbitarray

Auto increment in MongoDB to store sequence of Unique User ID

I am making a analytics system, the API call would provide a Unique User ID, but it's not in sequence and too sparse.

I need to give each Unique User ID an auto increment id to mark a analytics datapoint in a bitarray/bitset. So the first user encounters would corresponding to the first bit of the bitarray, second user would be the second bit in the bitarray, etc.

So is there a solid and fast way to generate incremental Unique User IDs in MongoDB?

Solution

  • You can, but you should not https://web.archive.org/web/20151009224806/http://docs.mongodb.org/manual/tutorial/create-an-auto-incrementing-field/

    Each object in mongo already has an id, and they are sortable in insertion order. What is wrong with getting collection of user objects, iterating over it and use this as incremented ID? Er go for kind of map-reduce job entirely