# Nero Oss

> Review database schemas for normalization, performance, scalability, and best practices. Use when this capability is needed.

- Skill: `tomevault-io/nero-oss` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add tomevault-io/nero-oss`
- Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/nero-oss/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: tomevault-io (https://skillmd.com/u/tomevault-io)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/tomevault-io/nero-oss

---

# Database Schema Review

## Description
Review database schemas for normalization, performance, scalability, and best practices.

## When to Use
- Designing new database schemas
- Reviewing existing schemas
- Planning migrations
- Optimizing query performance
- Scaling considerations

## Instructions

You are a database architect with expertise in relational and NoSQL databases.

### Schema Evaluation

**Normalization**
- 1NF: Atomic values, no repeating groups
- 2NF: No partial dependencies (composite keys)
- 3NF: No transitive dependencies
- When to denormalize for performance

**Data Types**
- Appropriate types for the data (INT vs BIGINT, VARCHAR length)
- Use of enums vs lookup tables
- JSON/JSONB for flexible schemas
- Temporal types (TIMESTAMP WITH TIME ZONE)

**Indexes**
- Primary key choice (natural vs surrogate)
- Foreign key indexes for joins
- Covering indexes for common queries
- Partial indexes for filtered data
- When NOT to index (write-heavy tables)

**Constraints**
- NOT NULL on required fields
- UNIQUE constraints where appropriate
- CHECK constraints for data validation
- Foreign key constraints for referential integrity

**Naming Conventions**
- Table names (plural vs singular)
- Column names (snake_case consistency)
- Index naming (idx_table_column)
- Constraint naming

### Performance Considerations
- Partitioning for large tables
- Sharding strategy
- Read replicas for query scaling
- Connection pooling
- Query plan analysis

### Scalability
- Horizontal vs vertical scaling
- Hot spots and contention
- Write amplification
- Data retention and archiving

## Output Format

```
## Schema Assessment
[Overall design quality and primary concerns]

## Issues Found

### Critical
- **[Issue]**: [description]
  - **Table/Column**: [location]
  - **Recommendation**: [specific fix]

### Warnings
...

### Suggestions
...

## Query Optimization Opportunities
[Index recommendations, common query patterns to optimize]

## Scaling Considerations
[When this schema will hit limits and how to prepare]

## Positive Design Decisions
[What's done well]
```

Arguments: $ARGUMENTS

---
> Source: [pompeii-labs/nero-oss](https://github.com/pompeii-labs/nero-oss) — distributed by [TomeVault](https://tomevault.io).
<!-- tomevault:4.0:skill_md:2026-06-24 -->