DB Design for a Startup: Keep It Simple

You aren't Google, and that's perfectly fine

95% of applications will never need distributed databases. Start with PostgreSQL and focus on your product.

Start Simple: The Reality of Database Scale

PostgreSQL on AWS RDS/Cloud SQL/Azure will handle your first 10 million users.

Start Simple: Database Reality Check Most applications never need distributed databases 95% of Apps Managed PostgreSQL < 100GB Data < 1000 requests/sec PostgreSQL 🌍 Data Residency Solved EU (GDPR) • US • Asia-Pacific Just select region in console Providers: AWS RDS • Google Cloud SQL Azure Database • Supabase $25 - $100/month Zero ops, full compliance Top 5% of Apps Scaled PostgreSQL 100GB - 10TB Data 1K - 10K requests/sec Primary + Replicas Read 1 Read 2 Cache Example: Notion PostgreSQL + replicas at $10B valuation Solutions: Aurora • AlloyDB • Citus Still single logical database $500 - $5K/month Some ops, mostly managed Top 1% Only Truly Distributed > 10TB Data > 10K requests/sec Shard 1 Shard 2 Shard 3 ...N ⚠️ High operational complexity Actually needed when: • Global < 50ms latency required • Database team of 5+ engineers Examples: Spanner • DynamoDB • Cassandra $10K+/month Plus dedicated ops team 💡 Pro tip: Let managed services handle regions, compliance, and scaling. Focus on your product.

Examples

Company Exit Value Database Strategy
Instagram $1B PostgreSQL until acquisition
WhatsApp $19B PostgreSQL handled 900M users
Notion $10B valuation Still on PostgreSQL + replicas
Stack Overflow Still thriving 4 SQL Servers, 1.3B pageviews/month
💰 The $120B Database Market (2024) $50B Single Instance PostgreSQL • MySQL RDS • Azure SQL • Cloud SQL Millions of apps $70B Distributed/Scale Aurora • Spanner • DynamoDB BigQuery • Snowflake • Cosmos DB Trillions in transactions 95% of apps 90% of revenue Top 7 vendors control 91% of $120B market AWS $27B Microsoft $25B Oracle $18B Google $10B Snow $4B IBM $4B DBX $3B 100+ Others ~$10B The paradox: 95% of apps run on single instances, but the top 1% drive most database revenue Source: Gartner 2023 Database Market Analysis

Common Startup Mistakes to Avoid

Mistake 1: Over-Engineering from Day One

# DON'T DO THIS for your MVP
architecture = {
    'microservices': 12,
    'databases': ['PostgreSQL', 'MongoDB', 'Redis', 'Elasticsearch'],
    'message_queues': ['Kafka', 'RabbitMQ'],
    'orchestration': 'Kubernetes',
}

# DO THIS instead
architecture = {
    'monolith': 'PostgreSQL + React',
    'deployment': 'Vercel' or 'GCP' or 'AWS',
}

Mistake 2: DIY Database Management

Every hour spent on database ops is an hour not spent on your product. Use AWS RDS, Cloud SQL, or Azure Database. Period.