Error: 224/225 exercises failed with NOT NULL constraint violations
Root cause: exercises table requires BOTH goal AND execution (NOT NULL)
Reality: Many wiki exercises have only ONE of these fields
Migration 019:
- ALTER COLUMN goal DROP NOT NULL
- ALTER COLUMN execution DROP NOT NULL
- ADD CHECK constraint: (goal IS NOT NULL OR execution IS NOT NULL)
This allows:
✓ Exercises with only goal
✓ Exercises with only execution
✓ Exercises with both
✗ Exercises with neither (CHECK constraint fails)
Import validation already correct (line 312):
required_ok = bool(mapped.get('goal') or mapped.get('execution'))
DB schema was blocking valid exercises.
