@mojojs/sql/README.md

SQL generator

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Safely generate and compose SQL statements with tagged template literals. Written in TypeScript.

```js
import {sql} from '@mojojs/sql';

// {text: 'SELECT * FROM users WHERE name = $1', values: ['sebastian']}
const {text, values} = sql`SELECT * FROM users WHERE name = ${'sebastian'}`.toQuery();
```

To prevent SQL injection attacks, all interpolated values become placeholders in the generated query. Partial
statements can even be used recursively to build more complex queries.

```js
const role = 'admin';
const partialQuery = sql`AND role = ${role}`;
const name = 'root';

// {text: 'SELECT * FROM users WHERE name = $1 AND role = $2', values: ['root', 'admin']}
const {text, values} = sql`SELECT * FROM users WHERE name = ${name} ${partialQuery}`.toQuery();
```

Make partial statements optional to dynamically generate `WHERE` clauses.

```js
const optionalPart = foo === true ? sql`AND foo IS NOT NULL` : sql``;
const {text, values} = sql`SELECT * FROM users WHERE name = ${'sebastian'} ${optionalPart}`.toQuery();
```

And if you need a little more control over the generated SQL query, you can of course also bypass safety features with
the tagged template literal `sqlUnsafe`. But make sure to handle unsafe values yourself with appropriate escaping
functions for your database. For PostgreSQL there are `escapeLiteral` and `escapeIdentifier` functions included with
this package.

```js
import {sql, sqlUnsafe, escapeLiteral} from '@mojojs/sql';

const role = 'role = ' + escapeLiteral('power user');
const partialQuery = sqlUnsafe`AND ${role}`;
const name = 'root';

// {text: "SELECT * FROM users WHERE name = $1 AND role = 'power user'", values: ['root']}
const {text, values} = sql`SELECT * FROM users WHERE name = ${name} ${partialQuery}`.toQuery();
```

For databases that do not support numbered placeholders like `$1` and `$2`, you can set a custom character with the
`placeholder` option.

```js
// {text: 'SELECT * FROM users WHERE name = ?', values: ['root']}
const {text, values} = sql`SELECT * FROM users WHERE name = ${'root'}`.toQuery({placeholder: '?'});
```

### Editor Support

* [Visual Studio Code](https://marketplace.visualstudio.com/items?itemName=kraih.javascript-tmpl-support)

## Installation

All you need is Node.js 16.0.0 (or newer).

```
$ npm install @mojojs/sql
```

## Support

If you have any questions the documentation might not yet answer, don't hesitate to ask in the
[Forum](https://github.com/mojolicious/mojo.js/discussions), on [Matrix](https://matrix.to/#/#mojo:matrix.org), or
[IRC](https://web.libera.chat/#mojo).