| 摘要 |
Dynamic inheritance for data in a replicated tree structured database which is dynamically inherited from parent objects is provided by only replicating original modifications, and then causing each system to propagate inherited information across it's local tree of objects. When a change to a security descriptor or a reparenting of objects is received, a breadth first tree traversal is used to find all the affected objects. An ID list is incrementally deleted as each object is updated. A security descriptor propagator queue is used to track the progress of updates, and items are taken off the list only after they are committed to the database. A gate is used to ensure that that transactions which add new objects and the security descriptor propagation transactions which write new security descriptors are mutually exclusive. A new data structure for the propagation queue comprises a table having a unique, incrementing number representing an order, an identifier of the node to begin on, a flag indicting whether the item may be trimmed a client id, an order index used to find the next element in the queue and a trim index which tracks all trimmable nodes.
|
