oracledb_cdc: Improve snapshot performance (~50%) by reusing seeded schema metadata - #4695
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josephwoodward
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August 13, 2026 10:23
josephwoodward
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josephwoodward
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Jeffail
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Currently when snapshotting, every row rebuilds the table schema from metadata. This change checks to see if the column metadata is the same as the previous row by pointer (ie, same slice - which is likely if snapshotting), and will reuse the generated schema.
The results below are without
PREFETCH_ROWSconfigured.Before:
2M rows, avg. 13MB/s took 40 seconds
After:
2M rows, avg. 25MB/s took 20 seconds (~50% improvement)