Page History

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There may be a large number of historical DDL operations, and each commit file may contain more and more historical versions of schemas. This requires a cleanup mechanism to set the number of schema historical versions retained. If the schema changes occur again, the historical version beyond the policy will not be recorded in the commit file.The cleaning policy is specific to tables, and each table can set a different count of version retained.

Evolution of the data file：

The data file field name is mapped to the Schema Metada field ID.

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