Capped collections are fixed-size collections that support high-throughput ... As a result, queries do not need an index to return documents in insertion order. Fix dbhash cache issue for config servers SERVER-11421. ... Previous versions of MongoDB did not enforce this requirement, and existing ... I have some scripts which update, mongoDb records which look like this : ... MongoDB does not have a method for "fixed-length" arrays. With MongoDB 2.4, one of the cool features is atomic fixed length arrays. To use, combine the $push and $slice functionality.
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