Terms and Techniques

This page explains some terms used in MongoMVCC and the related implementation techniques.

Collection

A collection in MongoMVCC is similar to a collection in MongoDB. It is a group of documents. The difference is that each branch in the MongoMVCC tree may contain its own collections. You can obtain a collection as follows:

VDatabase db = ...
VBranch master = db.checkout(VConstants.MASTER);
VCollection coll = master.getCollection("persons");

In order to uniquely identify objects in the database, MongoMVCC automatically assigns new _id and uid attributes to each document inserted into a collection. _id is used to identify a certain version of a document. The uid attribute identifies all versions of the same document.

Please do not assign your own identifiers for _id and uid. The library currently does not prevent you from doing so, but you might accidentally corrupt your data. If you need a special identifier, please use another attribute.

Commit

TODO also include CID

Tree

Branch

Index

Large Collection