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  1. MariaDB Server
  2. MDEV-17035

Support ALGORITHM=NOCOPY for CHANGE virtual column expression

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      Currently, the ALTER TABLE operation ALTER_STORED_GCOL_EXPR (changing the expression of a generated stored column, or materialized virtual column) is only supported by ALGORITHM=COPY, which does a full rebuild of the table.

      We could support the operation with ALGORITHM=NOCOPY by validating all data and executing UPDATE of the data. Concurrent non-locking MVCC reads would be possible, but concurrent writes to the table could lead to locking conflicts.

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              Assignee:
              marko Marko Mäkelä
              Reporter:
              marko Marko Mäkelä
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