managed-databases

# Managed Databases Skill

## PostgreSQL

### Provisioning

```bash
# Create production cluster
doctl databases create prod-pg \
  --engine pg \
  --version 16 \
  --region nyc1 \
  --size db-s-2vcpu-4gb \
  --num-nodes 2 \
  --private-network-uuid <vpc-id>
```

### Connection Patterns

**Node.js (pg):**

```typescript
import { Pool } from 'pg';

const pool = new Pool({
  connectionString: process.env.DATABASE_URL,
  ssl: {
    rejectUnauthorized: true,
    ca: process.env.DATABASE_CA_CERT,
  },
  max: 20,
  idleTimeoutMillis: 30000,
  connectionTimeoutMillis: 2000,
});

// Query
const { rows } = await pool.query('SELECT * FROM users WHERE id = $1', [id]);

// Transaction
const client = await pool.connect();
try {
  await client.query('BEGIN');
  await client.query('INSERT INTO users(name) VALUES($1)', ['John']);
  await client.query('COMMIT');
} catch (e) {
  await client.query('ROLLBACK');
  throw e;
} finally {
  client.release();
}
```

**Python (psycopg2):**

```python
import psycopg2
from psycopg2.extras import RealDictCursor

conn = psycopg2.connect(
    os.environ['DATABASE_URL'],
    sslmode='require',
    sslrootcert='ca-certificate.crt',
    cursor_factory=RealDictCursor
)

with conn.cursor() as cur:
    cur.execute("SELECT * FROM users WHERE id = %s", (user_id,))
    user = cur.fetchone()
```

**Prisma:**

```prisma
datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}
```

**Drizzle:**

```typescript
import { drizzle } from 'drizzle-orm/node-postgres';
import { Pool } from 'pg';

const pool = new Pool({
  connectionString: process.env.DATABASE_URL,
  ssl: { rejectUnauthorized: true },
});

export const db = drizzle(pool);
```

### Connection Pooling

```bash
# Create connection pool
doctl databases pool create <cluster-id> app-pool \
  --db myapp_production \
  --user app_user \
  --mode transaction \
  --size 25
```

## Redis/Valkey

### Provisioning

```bash
doctl databases create prod-cache \
  --engine valkey \
  --version 7 \