knex/documentation

Knex Documentation Builder (Moved to https://github.com/knex/knex)

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();

documentation's Issues

Logger.deprecate signature

Documentation says that the Logger.deprecate method signature is

deprecate(message) {},

while according to source code and types it should be

deprecate?: (method: string, alternative: string) => void;