Fix --split-tables-larger-than resume guidance#36
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The blanket "never use with --resume" was wrong. The truncation risk only exists when COPY is still in progress. If COPY completed and the failure was in indexes/CDC, resume with the same value is safe and required by catalog validation.
DmitriiAn
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Apr 1, 2026
| /usr/lib/postgresql/17/bin/pgcopydb clone \ | ||
| --follow \ | ||
| --plugin wal2json \ | ||
| --resume \ |
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the script does not support switching between --resume and --restart flags. according to the README users should be able to do that
DmitriiAn
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Apr 1, 2026
| This backs up the SQLite catalog before resuming. It uses `--not-consistent` to allow resuming from a mid-transaction state, and intentionally omits `--split-tables-larger-than` because pgcopydb truncates the entire table before checking split parts on resume, which causes data loss. | ||
| This backs up the SQLite catalog before resuming and uses `--not-consistent` to allow resuming from a mid-transaction state. | ||
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| **Choosing between `--resume` and `--restart`:** |
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as a user, I am not sure where to apply --resume and --restart because it wasn't shown in the examples above
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Summary
--split-tables-larger-thanback toresume-migration.sh(matchingrun-migration.sh)--resumewith same value is safe (COPY supervisor doesn't run)--restartinstead (truncation risk for split tables)Test plan