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Problem:
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During InnoDB non-rebuild online alter operation, InnoDB set the
dummy log to clustered index online log. This can be used by
concurrent DML to identify whether the table undergoes online DDL.
InnoDB fails to reset the dummy log of clustered index in case
of error happened during prepare phase.

Solution:
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Reset the InnoDB clustered index online log in case of error during
prepare phase.