db-review

When this skill is invoked:

1. Read the target schema, migration, or query files in full.

1. Evaluate schema design:
2. [ ] All tables have a primary key
3. [ ] Tables have created_at and updated_at columns
4. [ ] Foreign key relationships defined with proper constraints
5. [ ] Column types are appropriate (don't use VARCHAR(255) for everything)
6. [ ] NULL vs NOT NULL is intentionally chosen and documented
7. [ ] Enum types used for fixed sets of values

1. Evaluate indexing strategy:
2. [ ] Every foreign key column is indexed
3. [ ] Columns in frequent WHERE, ORDER BY, or JOIN conditions are indexed
4. [ ] Composite indexes match the query patterns
5. [ ] No over-indexing (too many indexes slow writes)
6. [ ] Unique constraints used where business rules require uniqueness

1. Evaluate migration safety:
2. [ ] Migration is reversible (has a down/rollback script)
3. [ ] Adding columns with defaults is safe for zero-downtime
4. [ ] Removing columns uses soft-delete / multi-phase approach
5. [ ] Renaming columns uses multi-phase migration (add → backfill → drop old)
6. [ ] Large table operations consider locking implications

1. Evaluate data integrity:
2. [ ] Check constraints for value ranges where appropriate
3. [ ] No orphaned records possible (foreign keys or enforced at app layer)
4. [ ] Soft delete implemented (deleted_at) not hard delete for important records

1. Evaluate query quality (if queries provided):
2. [ ] No SELECT * in application queries
3. [ ] N+1 queries avoided (eager loading where needed)
4. [ ] Parameterized queries (no string concatenation)
5. [ ] Pagination on all list queries

1. Output the review:

## Database Review: [Schema/Migration Name]

### Schema Design: [CLEAN / ISSUES FOUND]
[List design problems]

### Indexes: [APPROPRIATE / MISSING / OVER-INDEXED]
[List index recommendations]

### Migration Safety: [SAFE / RISKY / BLOCKING]
[List migration risks and recommendations]

### Data Integrity: [ENFORCED / GAPS FOUND]
[List integrity concerns]

### Query Quality: [CLEAN / ISSUES FOUND]
[List query problems]

### Positive Observations
[What is well-designed]

### Required Changes
[Must-fix before applying]

### Suggestions
[Nice-to-have improvements]

### Verdict: [APPROVED / APPROVED WITH SUGGESTIONS / CHANGES REQUIRED]

Protocol

• Question: Auto-starts from argument (schema, migration, or query files)
• Options: Skip — single review path
• Decision: Skip — verdict is advisory
• Draft: Full review shown in conversation only
• Approval: Skip — read-only; no files written

Output

Deliver exactly:

• Schema score (X/6 design checks passing)
• Migration safety: SAFE / RISKY / BLOCKING with specific risks listed
• Required changes — must fix before applying migration (or "None")
• Verdict: APPROVED / APPROVED WITH SUGGESTIONS / CHANGES REQUIRED