1. A method of concurrency control for database transactions in a distributed database system comprising two or more nodes on a computer network, said method comprising: locally, with respect to a node, asserting a serialization ordering between a first transaction requesting to use a database resource locally and one or more other database transactions that have already used the database resource locally; including the serialization ordering within a local serialization graph, wherein the local serialization graph comprises a subset of all serialization orderings throughout the distributed database; and detecting cycles in a local serialization graph.