摘要 |
A database system includes a locking mechanism for an aggregate materialized view defined on base relations. In response to updates of a base relation, predefined locks are placed on the aggregate materialized view. With locking mechanisms, transaction concurrency is enhanced by enabling concurrent updates of the materialized view by plural transactions in certain cases, while avoiding the situation in which multiple tuples belonging to the same group are integrated as separate tuples into the aggregate materialized view.
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