Help Center/ GaussDB/ Distributed_8.x/ Storage Engine/ Ustore/ Storage Format/ UB-Tree

Updated on 2024-06-07 GMT+08:00

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UB-Tree

The B-tree is enhanced as follows, which is referred to as UB-tree.

The transaction information is added to UB-tree indexes to perform MVCC independently. This increases the proportion of IndexOnlyScan and greatly reduces the number of times that TABLE ACCESS BY INDEX ROWID is executed.
VACUUM is not the only way to clear historical data. Spaces are recycled independently. Indexes are decoupled from heap tables and can be cleared independently. The I/O stability is better.

PCR UB-Tree
PCR UB-Tree

Parent topic: Storage Format

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