Help Center/ GaussDB/ Feature Guide(Distributed_V2.0-3.x)/ Storage Engine/ Ustore/ Storage Format/ Index/ RCR UB-Tree Visibility Mechanism

Updated on 2025-08-22 GMT+08:00

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RCR UB-Tree Visibility Mechanism

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Multi-version management and visibility check of index data are supported to identify tuples of historical versions and recycle them. In addition, the visibility check at the index layer greatly improves the probability of index scan and index-only scan.
In addition to the index insertion operation, an index deletion operation is added to mark an index tuple corresponding to a deleted or modified tuple.

Parent topic: Index

Previous topic: Row Consistency Read (RCR) UB-tree Multi-Version Management

Next topic: Inserting, Deleting, Updating, and Scanning UB-Tree

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