MongoDB IDs - will two collections have the same ids? -


this question has answer here:

ok, have members collection , pet members collection, understand basic workings on how ids generated, there chance id gets assigned pets collection same members collection?

the reason ask, improving social networking site, uses mongodb @ core. while social site give each pet id ( case if owner buys id ) use "_id" or '$id' main id in our database.

so question possible knowing 2 totally separate collections end same id each other? - don't want.

mongodb's objectid unlikely collide. contains counter, random number, process id, etc. objectids generated on different servers have different random number, process id, etc. objectids generated on same server differ in counter part.


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