API Reference
See README.md for overview, configuration.md for setup.
Binding Interface
interface Hyperdrive {
connectionString: string // PostgreSQL
// MySQL properties:
host: string
port: number
user: string
password: string
database: string
}
interface Env {
HYPERDRIVE: Hyperdrive
}
Generate types: npx wrangler types (auto-creates worker-configuration.d.ts from wrangler.jsonc)
PostgreSQL (node-postgres) - RECOMMENDED
import { Client } from 'pg' // pg@^8.17.2
export default {
async fetch(req: Request, env: Env): Promise<Response> {
const client = new Client({ connectionString: env.HYPERDRIVE.connectionString })
try {
await client.connect()
const result = await client.query('SELECT * FROM users WHERE id = $1', [123])
return Response.json(result.rows)
} finally {
await client.end()
}
},
}
⚠️ Workers connection limit: 6 per Worker invocation - use connection pooling wisely.
PostgreSQL (postgres.js)
import postgres from 'postgres' // postgres@^3.4.8
const sql = postgres(env.HYPERDRIVE.connectionString, {
max: 5, // Limit per Worker (Workers max: 6)
prepare: true, // Enabled by default, required for caching
fetch_types: false, // Reduce latency if not using arrays
})
const users = await sql`SELECT * FROM users WHERE active = ${true} LIMIT 10`
⚠️ prepare: true is enabled by default and required for Hyperdrive caching. Setting to false disables prepared statements + cache.
MySQL (mysql2)
import { createConnection } from 'mysql2/promise' // mysql2@^3.16.2
const conn = await createConnection({
host: env.HYPERDRIVE.host,
user: env.HYPERDRIVE.user,
password: env.HYPERDRIVE.password,
database: env.HYPERDRIVE.database,
port: env.HYPERDRIVE.port,
disableEval: true, // ⚠️ REQUIRED for Workers
})
const [results] = await conn.query('SELECT * FROM users WHERE active = ? LIMIT ?', [true, 10])
ctx.waitUntil(conn.end())
⚠️ MySQL support is less mature than PostgreSQL - expect fewer optimizations and potential edge cases.
Query Caching
Cacheable:
SELECT * FROM posts WHERE published = true;
SELECT COUNT(*) FROM users;
NOT cacheable:
-- Writes
INSERT/UPDATE/DELETE
-- Volatile functions
SELECT NOW();
SELECT random();
SELECT LASTVAL(); -- PostgreSQL
SELECT UUID(); -- MySQL
Cache config:
- Default:
max_age=60s,swr=15s - Max
max_age: 3600s - Disable:
--caching-disabled=true
Multiple configs pattern:
// Reads: cached
const sqlCached = postgres(env.HYPERDRIVE_CACHED.connectionString)
const posts = await sqlCached`SELECT * FROM posts ORDER BY views DESC LIMIT 10`
// Writes/time-sensitive: no cache
const sqlNoCache = postgres(env.HYPERDRIVE_NO_CACHE.connectionString)
const orders = await sqlNoCache`SELECT * FROM orders WHERE created_at > NOW() - INTERVAL 5 MINUTE`
ORMs
Drizzle:
import { drizzle } from 'drizzle-orm/postgres-js' // drizzle-orm@^0.45.1
import postgres from 'postgres'
const client = postgres(env.HYPERDRIVE.connectionString, { max: 5, prepare: true })
const db = drizzle(client)
const users = await db.select().from(users).where(eq(users.active, true)).limit(10)
Kysely:
import { Kysely, PostgresDialect } from 'kysely' // kysely@^0.27+
import postgres from 'postgres'
const db = new Kysely({
dialect: new PostgresDialect({
postgres: postgres(env.HYPERDRIVE.connectionString, { max: 5, prepare: true }),
}),
})
const users = await db.selectFrom('users').selectAll().where('active', '=', true).execute()
See patterns.md for use cases, gotchas.md for limits.