README.md

Preql.js

Preql is a library to make writing SQL in javascript bearable, inspired by Yesql.

##Rationale##

Sometimes, when accessing a SQL database in Javascript, you don't neccesarily want or need an ORM. But, writing something like

function getPost(id){
	client.query('SELECT * FROM posts WHERE id=$1',[id]);
}

Not only gets repetitive for multiple models, it's hard to read, there's no syntax highlighting, and multiline strings are annoying to format.

Enter Preql

##Usage##

To use Preql, have a file with your sql query:

SELECT *
FROM posts
WHERE author = 'John Doe'
LIMIT 10;

(Note that while this example uses postgres syntax, preql works with any sql database).

Then, in your javascript file, call preql and now it can be used as a regular javascript function.

var preql = require('preql');
var pg = require('pg');

var getPosts = preql.makeQuery('./some/directory/get_posts.sql');

getPosts(client.query.bind(client), function(err,result){
	console.log(result);
});

The functions generated by preql take three parameters. The first is the query function, typically generated by your database client. So where you would normally say

client.query('SELECT * FROM posts',callback);

with preql you would write

getPosts(client.query.bind(client),callback);

The reason you have to call .bind(client) is to compensate for javascript's lexical scoping, allowing the query function to act normally in a closure.

makeQueries

Preql also allows you to recursively require an entire directory of files, creating queries out of the .sql files in that directory. For example, if you had a directory like

/queries
/users
  find.sql
	getPosts.sql
	createPost.sql
	file.txt

when you call

preql.makeQueries('./queries');

it will return { getPosts: [Function], createPosts: [Function], users: { find: [Function] } }

Development

To install: npm install preql

Presql uses mocha and should for tests, run npm test to run the test suite.

##Todo##

• Allow for multiple queries per file

Written by Michael Fine