knex
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A batteries-included SQL query & schema builder for PostgresSQL, MySQL, CockroachDB, MSSQL and SQLite3
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# [knex.js](https://knex.github.io/documentation/)
[](https://npmjs.org/package/knex)
[](https://npmjs.org/package/knex)
[](https://coveralls.io/r/knex/knex?branch=master)
[](https://libraries.io/npm/knex)
[](https://gitter.im/tgriesser/knex)
> **A SQL query builder that is _flexible_, _portable_, and _fun_ to use!**
A batteries-included, multi-dialect (PostgreSQL, MariaDB, MySQL, CockroachDB, MSSQL, SQLite3, Oracle (including Oracle Wallet Authentication)) query builder for
Node.js, featuring:
- [transactions](https://knexjs.org/guide/transactions.html)
- [connection pooling](https://knexjs.org/guide/#pool)
- [streaming queries](https://knexjs.org/guide/interfaces.html#streams)
- both a [promise](https://knexjs.org/#Interfaces-Promises) and [callback](https://knexjs.org/guide/interfaces.html#callbacks) API
- a [thorough test suite](https://github.com/knex/knex/actions)
Node.js versions 16+ are supported.
- Take a look at the [full documentation](https://knexjs.org/) to get started!
- Browse the [list of plugins and tools](https://github.com/knex/knex/blob/master/ECOSYSTEM.md) built for knex
- Check out our [recipes wiki](https://github.com/knex/knex/wiki/Recipes) to search for solutions to some specific problems
- In case of upgrading from an older version, see [migration guide](https://github.com/knex/knex/blob/master/UPGRADING.md)
You can report bugs and discuss features on the [GitHub issues page](https://github.com/knex/knex/issues) or send tweets to [@kibertoad](http://twitter.com/kibertoad).
For support and questions, join our [Gitter channel](https://gitter.im/tgriesser/knex).
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](https://michaelavila.com/knex-querylab/)
## Local Development Setup
### Prerequisites
- Node.js 16+
- Python 3.x with `setuptools` installed (required for building native dependencies like `better-sqlite3`)
Python 3.12+ removed the built-in `distutils` module. If you encounter a `ModuleNotFoundError: No module named 'distutils'` error during `npm install`, install `setuptools` for the Python version used by node-gyp:
```bash
pip install setuptools
```
- **Windows only:** [Visual Studio Build Tools](https://visualstudio.microsoft.com/visual-cpp-build-tools/) with the "Desktop development with C++" workload
### Install dependencies
```bash
npm install
```
## Examples
We have several examples [on the website](http://knexjs.org). Here is the first one to get you started:
```js
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
```ts
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',
},
useNullAsDefault: true,
};
const knexInstance = knex(config);
knexInstance<User>('users')
.select()
.then((users) => {
console.log(users);
})
.catch((err) => {
console.error(err);
})
.finally(() => {
knexInstance.destroy();
});
```
## 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:
```js
import { knex } from 'knex/knex.mjs';
```
You can also just do the default import:
```js
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:
```js
/**
* @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();
```