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- DbDumper::dumpStep(): tables are dumped until the step's deadline in one REPEATABLE READ transaction and resumed at the last primary key in the next step; the running table checksum is carried over. A dump that fits in one step is fully consistent, otherwise the snapshot records dbConsistent=false. BackupService uses it, so the database phase no longer needs one long request (hosted Nextcloud, web cron) - restore inserts 100 rows per statement and leaves tables whose checksum already matches the dump untouched - spike C: 30-step dump gives the same checksums as the one-shot dump; restore rewrote only the 3 damaged tables of 147; 300k-row table restored in 14.6 s instead of 46 s