Help Center/ GaussDB/ Feature Guide(Distributed_V2.0-3.x)/ Storage Engine/ Ustore/ Storage Format/ Relation/ PbPCR Heap Visibility Mechanism

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

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PbPCR Heap Visibility Mechanism

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Currently, only row consistency read is supported. In the future, CR page construction and page consistency read will be supported, greatly improving the sequence scanning efficiency.
Space can be reused after data deletion transactions are committed without waiting for oldestxmin, increasing the space utilization. Old snapshots can be obtained from undo records.

Parent topic: Relation

Previous topic: Page-based Row Consistency Read (PbRCR) Heap Multi-Version Management

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