knex, libsql, pg-promise, and sequelize are all JavaScript libraries used to interact with relational databases from Node.js applications, but they serve different roles and make different trade-offs. knex is a SQL query builder that supports multiple databases and provides schema migration tools. libsql is a lightweight client specifically for SQLite-compatible databases, including Turso and Cloudflare D1. pg-promise is a PostgreSQL-focused library that wraps the native pg driver with promises and additional utilities. sequelize is a full-featured ORM (Object-Relational Mapper) that abstracts SQL behind model definitions and supports multiple databases including PostgreSQL, MySQL, SQLite, and Microsoft SQL Server.
Choosing a Node.js Database Client: knex vs libsql vs pg-promise vs sequelize
When building backend services in Node.js, picking the right database client affects everything — from development speed to runtime performance and deployment flexibility. The four packages under review (knex, libsql, pg-promise, sequelize) represent distinct approaches: query builders, lightweight clients, driver wrappers, and full ORMs. Let’s compare them through real engineering lenses.
🗃️ Core Philosophy: What Problem Does Each Solve?
knex is a query builder, not an ORM. It lets you construct SQL queries programmatically while still giving you escape hatches to write raw SQL. It includes a powerful migration system.
// knex: Build queries with chaining
const users = await knex('users')
.where('age', '>', 18)
.select('id', 'name');
libsql is a minimal client for SQLite-compatible databases that speak the libSQL protocol (including Turso and Cloudflare D1). It’s designed for edge runtimes where traditional TCP connections aren’t available.
// libsql: Execute against Turso or D1
import { createClient } from '@libsql/client';
const client = createClient({ url: "libsql://..." });
const result = await client.execute("SELECT * FROM users WHERE age > ?", [18]);
pg-promise is a promise-enhanced wrapper around the pg (node-postgres) driver. It adds query formatting, transactions, and task management while staying close to raw PostgreSQL.
// pg-promise: Use parameterized queries with promises
const users = await db.any('SELECT id, name FROM users WHERE age > $1', [18]);
sequelize is a full ORM. You define models in JavaScript, and it generates and executes SQL behind the scenes, handling relationships, validations, and lifecycle hooks.
// sequelize: Fetch via model methods
const users = await User.findAll({
attributes: ['id', 'name'],
where: { age: { [Op.gt]: 18 } }
});
🔌 Database Support: Where Can You Deploy?
knex supports PostgreSQL, MySQL, MariaDB, SQLite3, Oracle, and MSSQL. You can switch databases by changing the configuration.
// knex: Same code, different DB
const knex = require('knex')({
client: 'pg', // or 'mysql2', 'sqlite3', etc.
connection: { /* ... */ }
});
libsql only works with databases that implement the libSQL protocol — primarily SQLite, Turso, and Cloudflare D1. It does not support PostgreSQL, MySQL, or other traditional RDBMS.
// libsql: Only libSQL-compatible endpoints
const client = createClient({
url: "libsql://your-db.turso.io",
authToken: "your-token"
});
pg-promise is PostgreSQL-only. It builds directly on the pg driver and assumes Postgres-specific features like $1 placeholders and JSONB.
// pg-promise: PostgreSQL syntax only
await db.one('SELECT $1::jsonb AS data', [{ key: 'value' }]);
sequelize supports PostgreSQL, MySQL, MariaDB, SQLite, and MSSQL — similar breadth to Knex, but with ORM-specific dialect quirks.
// sequelize: Dialect-agnostic model definition
const User = sequelize.define('User', {
name: DataTypes.STRING,
age: DataTypes.INTEGER
});
⚙️ Migrations and Schema Management
knex includes a built-in CLI and API for writing and running migrations. This is one of its strongest features.
// knex migration
exports.up = function(knex) {
return knex.schema.createTable('users', table => {
table.increments('id');
table.string('name');
});
};
libsql has no built-in migration system. You must manage schema changes manually via SQL scripts or external tools.
// libsql: Manual schema updates
await client.execute(`
CREATE TABLE IF NOT EXISTS users (
id INTEGER PRIMARY KEY,
name TEXT
)
`);
pg-promise does not include migrations. Most teams pair it with standalone tools like db-migrate or custom scripts.
// pg-promise: Run migration SQL directly
await db.none(`
CREATE TABLE IF NOT EXISTS users (
id SERIAL PRIMARY KEY,
name VARCHAR(255)
)
`);
sequelize provides a migration CLI (sequelize-cli) and model synchronization, though sync() is discouraged in production.
// sequelize migration
module.exports = {
up: async (queryInterface, Sequelize) => {
await queryInterface.createTable('Users', {
id: { type: Sequelize.INTEGER, primaryKey: true, autoIncrement: true },
name: Sequelize.STRING
});
}
};
🔄 Transactions and Connection Handling
knex supports transactions with explicit begin/commit/rollback control.
// knex transaction
await knex.transaction(async (trx) => {
await trx('users').insert({ name: 'Alice' });
await trx('profiles').insert({ user_id: 1 });
});
libsql supports transactions via SQL statements or batched writes, but not programmatic transaction blocks like traditional clients.
// libsql: Transaction via SQL
await client.execute("BEGIN;");
try {
await client.execute("INSERT INTO users (name) VALUES ('Alice');");
await client.execute("INSERT INTO profiles (user_id) VALUES (1);");
await client.execute("COMMIT;");
} catch (e) {
await client.execute("ROLLBACK;");
throw e;
}
pg-promise has first-class transaction support with automatic rollback on error.
// pg-promise transaction
db.tx(async t => {
await t.none('INSERT INTO users(name) VALUES($1)', 'Alice');
await t.none('INSERT INTO profiles(user_id) VALUES($1)', 1);
});
sequelize offers transaction support through its own API.
// sequelize transaction
const t = await sequelize.transaction();
try {
await User.create({ name: 'Alice' }, { transaction: t });
await Profile.create({ userId: 1 }, { transaction: t });
await t.commit();
} catch (error) {
await t.rollback();
throw error;
}
📦 Type Safety and Developer Experience
knex has decent TypeScript support, but query results are often typed as any[] unless you use third-party helpers like knex-typescript.
// knex: Manual typing often needed
interface User { id: number; name: string; }
const users: User[] = await knex.select('*').from('users');
libsql provides excellent first-party TypeScript support with typed results based on your query.
// libsql: Built-in types
const result = await client.execute<{ id: number; name: string }>(
"SELECT id, name FROM users WHERE age > ?",
[18]
);
pg-promise supports TypeScript via ambient declarations, but result typing requires manual annotation or helper functions.
// pg-promise: Manual typing
interface User { id: number; name: string; }
const users: User[] = await db.any('SELECT id, name FROM users');
sequelize has strong TypeScript support when defining models with static typing.
// sequelize: Typed models
class User extends Model<InferAttributes<User>, InferCreationAttributes<User>> {
declare id: number;
declare name: string;
}
const users = await User.findAll(); // Fully typed
🧪 Testing and Mocking
knex can be mocked by swapping the database connection or using libraries like jest.mock(), but its fluent API makes deep mocking tricky.
libsql’s simple execute interface is easy to mock since it’s just a method call returning a promise.
// libsql mock
jest.mock('@libsql/client', () => ({
createClient: () => ({
execute: jest.fn().mockResolvedValue({ rows: [] })
})
}));
pg-promise can be mocked at the query level using its initialization options or by replacing the db object.
sequelize is harder to mock due to its complex internal state; many teams use in-memory SQLite for tests instead.
🚫 When Not to Use Each
- Avoid
knexif you need strict type safety out of the box or are only using one database and want maximum performance. - Avoid
libsqlif you’re not using Turso, D1, or SQLite — it simply won’t work with PostgreSQL or MySQL. - Avoid
pg-promiseif you need to support multiple databases or want high-level abstractions like associations. - Avoid
sequelizeif you frequently need to write complex SQL, debug performance issues, or work in resource-constrained environments (ORMs add overhead).
📊 Summary Table
| Feature | knex | libsql | pg-promise | sequelize |
|---|---|---|---|---|
| Type | Query Builder | Lightweight Client | Driver Wrapper | Full ORM |
| Databases | Multi (PG, MySQL, etc.) | SQLite/Turso/D1 only | PostgreSQL only | Multi (PG, MySQL, etc.) |
| Migrations | ✅ Built-in | ❌ None | ❌ External only | ✅ CLI included |
| Transactions | ✅ Explicit | ✅ Via SQL | ✅ First-class | ✅ Supported |
| TypeScript | ⚠️ Manual typing | ✅ Excellent | ⚠️ Manual typing | ✅ Strong with setup |
| Raw SQL Escape Hatch | ✅ .raw() | ✅ Native | ✅ Native | ✅ .query() |
| Best For | Teams wanting SQL control + migrations | Edge apps on Turso/D1 | PG shops avoiding ORMs | Teams preferring models over SQL |
💡 Final Recommendation
- If you’re building a traditional backend with PostgreSQL and want minimal abstraction, go with
pg-promise. - If you’re deploying to Cloudflare Workers or using Turso,
libsqlis your only viable option among these. - If you need cross-database support and migrations without ORM complexity,
knexstrikes the best balance. - If your team prefers modeling data as JavaScript objects and accepts ORM trade-offs,
sequelizedelivers rich features out of the box.
Remember: the “best” tool depends entirely on your stack, team preferences, and deployment constraints — not hype or download counts.
- knex:
Choose
knexif you need a flexible, database-agnostic query builder with strong support for migrations and raw SQL when needed. It’s ideal when your team prefers writing explicit SQL-like queries but wants programmatic construction and cross-database compatibility without full ORM overhead. - sequelize:
Choose
sequelizeif you prefer working with JavaScript models instead of raw SQL, need features like associations, validations, and eager loading out of the box, and are willing to accept the performance and debugging trade-offs that come with heavy ORM abstraction. - pg-promise:
Choose
pg-promiseif you’re using PostgreSQL exclusively and want a thin, promise-based wrapper around the nativepgdriver with robust transaction support, query formatting, and error handling—without the abstraction layer of an ORM. - libsql:
Choose
libsqlif you’re building an application that uses SQLite, Turso, or Cloudflare D1 and want a minimal, modern client with first-class TypeScript support and HTTP-based connectivity. It’s best suited for edge environments or serverless deployments where traditional database drivers aren’t viable.
knex.js
A SQL query builder that is flexible, portable, and fun to use!
A batteries-included, multi-dialect (PostgreSQL, MySQL, CockroachDB, MSSQL, SQLite3, Oracle (including Oracle Wallet Authentication)) query builder for Node.js, featuring:
- transactions
- connection pooling
- streaming queries
- both a promise and callback API
- a thorough test suite
Node.js versions 12+ are supported.
- Take a look at the full documentation to get started!
- Browse the list of plugins and tools built for knex
- Check out our recipes wiki to search for solutions to some specific problems
- In case of upgrading from an older version, see migration guide
You can report bugs and discuss features on the GitHub issues page or send tweets to @kibertoad.
For support and questions, join our Gitter channel.
For knex-based Object Relational Mapper, see:
- https://github.com/Vincit/objection.js
- https://github.com/mikro-orm/mikro-orm
- https://bookshelfjs.org
To see the SQL that Knex will generate for a given query, you can use Knex Query Lab
Examples
We have several examples on the website. Here is the first one to get you started:
const knex = require('knex')({
client: 'sqlite3',
connection: {
filename: './data.db',
},
});
try {
// Create a table
await knex.schema
.createTable('users', (table) => {
table.increments('id');
table.string('user_name');
})
// ...and another
.createTable('accounts', (table) => {
table.increments('id');
table.string('account_name');
table.integer('user_id').unsigned().references('users.id');
});
// Then query the table...
const insertedRows = await knex('users').insert({ user_name: 'Tim' });
// ...and using the insert id, insert into the other table.
await knex('accounts').insert({
account_name: 'knex',
user_id: insertedRows[0],
});
// Query both of the rows.
const selectedRows = await knex('users')
.join('accounts', 'users.id', 'accounts.user_id')
.select('users.user_name as user', 'accounts.account_name as account');
// map over the results
const enrichedRows = selectedRows.map((row) => ({ ...row, active: true }));
// Finally, add a catch statement
} catch (e) {
console.error(e);
}
TypeScript example
import { Knex, knex } from 'knex';
interface User {
id: number;
age: number;
name: string;
active: boolean;
departmentId: number;
}
const config: Knex.Config = {
client: 'sqlite3',
connection: {
filename: './data.db',
},
};
const knexInstance = knex(config);
try {
const users = await knex<User>('users').select('id', 'age');
} catch (err) {
// error handling
}
Usage as ESM module
If you are launching your Node application with --experimental-modules, knex.mjs should be picked up automatically and named ESM import should work out-of-the-box.
Otherwise, if you want to use named imports, you'll have to import knex like this:
import { knex } from 'knex/knex.mjs';
You can also just do the default import:
import knex from 'knex';
If you are not using TypeScript and would like the IntelliSense of your IDE to work correctly, it is recommended to set the type explicitly:
/**
* @type {Knex}
*/
const database = knex({
client: 'mysql',
connection: {
host: '127.0.0.1',
user: 'your_database_user',
password: 'your_database_password',
database: 'myapp_test',
},
});
database.migrate.latest();