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However, it is possible that a staging graph for the latest commit is not yet available. This can happen when multiple updates are made to the same branch concurrently and the triplestore has not yet had enough time to COPY the snapshot graph to a dedicated staging graph. In this scenario, MMS5 uses the snapshot graph as an effective staging graph. This technique ultimately defers the COPY operation to a later time once any concurrent writes have settled. See
Effective staging graph example
For example, in the following diagram, e4a1c represents the latest commit at state #01 of the model. Notice how a snapshot graph and a staging graph materialize this same commit:
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