Note

Database recovery notes after failed table migration

Short operational notes on what failed, what was recovered first, and what to avoid next time.

22 July 2026·complete

Key points

• Recover the simplest high-value tables first.
• Do not assume a live table rebuild will finish just because it started.
• Preserve raw copies of the datadir before attempting salvage work.

What worked

• Rebuilding the service into a clean datadir
• Restoring MyISAM-backed tables first
• Keeping the broken source data separate from the rebuilt live database

What to do next time

• Take tested backups before schema migrations
• Avoid hot-path ALTER TABLE operations on large legacy tables
• Prefer staged migrations during a maintenance window