• AlaSQL is an unfunded open source project installed 650k+ times each month. Please donate your time. We appreciate any and all contributions we can get.

• Have a question? Ask The AlaSQL Bot or post on Stack Overflow.

AlaSQL

AlaSQL - ( à la SQL ) [ælæ ɛskju:ɛl] - is an open source SQL database for JavaScript with a strong focus on query speed and data source flexibility for both relational data and schemaless data. It works in the web browser, Node.js, and mobile apps.

This library is perfect for:

• Fast in-memory SQL data processing for BI and ERP applications on fat clients
• Easy ETL and options for persistence by data import / manipulation / export of several formats
• All major browsers, Node.js, and mobile applications

We focus on speed by taking advantage of the dynamic nature of JavaScript when building up queries. Real-world solutions demand flexibility regarding where data comes from and where it is to be stored. We focus on flexibility by making sure you can import/export and query directly on data stored in Excel (both .xls and .xlsx), CSV, JSON, TAB, IndexedDB, LocalStorage, and SQLite files.

The library adds the comfort of a full database engine to your JavaScript app. No, really - it's working towards a full database engine complying with most of the SQL-99 language, spiced up with additional syntax for NoSQL (schema-less) data and graph networks.

Traditional SQL Table

/* create SQL Table and add data */
alasql('CREATE TABLE cities (city string, pop number)');

alasql("INSERT INTO cities VALUES ('Paris',2249975),('Berlin',3517424),('Madrid',3041579)");

/* execute query */
var res = alasql('SELECT * FROM cities WHERE pop < 3500000 ORDER BY pop DESC');

// res = [ { "city": "Madrid", "pop": 3041579 }, { "city": "Paris", "pop": 2249975 } ]

Live Demo

Array of Objects

var data = [
    {a: 1, b: 10},
    {a: 2, b: 20},
    {a: 1, b: 30},
];

var res = alasql('SELECT a, SUM(b) AS b FROM ? GROUP BY a', [data]);

// res = [ { "a": 1, "b": 40},{ "a": 2, "b": 20 } ]

Live Demo

Spreadsheet

// file is read asynchronously (Promise returned when SQL given as array)
alasql([
    'SELECT * FROM XLS("./data/mydata") WHERE lastname LIKE "A%" and city = "London" GROUP BY name ',
])
    .then(function (res) {
        console.log(res); // output depends on mydata.xls
    })
    .catch(function (err) {
        console.log('Does the file exist? There was an error:', err);
    });

Bulk Data Load

alasql('CREATE TABLE example1 (a INT, b INT)');

// alasql's data store for a table can be assigned directly
alasql.tables.example1.data = [
    {a: 2, b: 6},
    {a: 3, b: 4},
];

// ... or manipulated with normal SQL
alasql('INSERT INTO example1 VALUES (1,5)');

var res = alasql('SELECT * FROM example1 ORDER BY b DESC');

console.log(res); // [{a:2,b:6},{a:1,b:5},{a:3,b:4}]

If you are familiar with SQL, it should be no surprise that proper use of indexes on your tables is essential for good performance.

Options

AlaSQL has several configuration options which change the behavior. It can be set via SQL statements or via the options object before using alasql.

If you're using NOW() in queries often, setting alasql.options.dateAsString to false speed things up. It will just return a JS Date object instead of a string representation of a date.

Installation

yarn add alasql                # yarn

npm install alasql             # npm

npm install -g alasql          # global install of command line tool

For the browsers: include alasql.min.js

<script src="https://cdn.jsdelivr.net/npm/alasql@4"></script>

Getting started

ESM Import (Recommended)

import alasql from 'alasql';

const data = [
    {name: 'Alice', age: 30},
    {name: 'Bob', age: 25},
];

const result = alasql('SELECT * FROM ? WHERE age > 26', [data]);
// [{ name: 'Alice', age: 30 }]

Using Plugins with .use()

Plugins and external libraries are registered with the .use() API:

import alasql from 'alasql';
import * as XLSX from 'xlsx';

// Register the XLSX library
alasql.use({xlsx: XLSX});

// Now you can use XLSX functions
const data = alasql('SELECT * FROM XLSX("mydata.xlsx")');
alasql('SELECT * INTO XLSX("output.xlsx") FROM ?', [data]);

The .use() API also accepts functions for custom extensions:

// Add custom functions
alasql.use(a => {
    a.fn.DOUBLE = x => x * 2;
});

alasql('SELECT DOUBLE(5)'); // Returns 10

See the "Getting started" section of the wiki

More advanced topics are covered in other wiki sections like "Data manipulation" and in questions on Stack Overflow

Other links:

• Documentation: Github wiki

• Library CDN: jsDelivr.com

• Feedback: Open an issue

• Try online: <a href="http://alasql.org/console?CREATE TABLE cities (city string, population number);INSERT INTO cities VALUES ('Rome',2863223), ('Paris',2249975),('Berlin',3517424), ('Madrid',3041579);SELECT * FROM cities WHERE population < 3500000 ORDER BY population DESC">Playground

• Website: alasql.org

Please note

All contributions are extremely welcome and greatly appreciated(!) - The project has never received any funding and is based on unpaid voluntary work: We really (really) love pull requests

The AlaSQL project depends on your contribution of code and may have bugs. So please, submit any bugs and suggestions as an issue.

Please check out the limitations of the library.

Performance

AlaSQL is designed for speed and includes some of the classic SQL engine optimizations:

• Queries are cached as compiled functions
• Joined tables are pre-indexed
• WHERE expressions are pre-filtered for joins

See more performance-related info on the wiki

Features you might like

Traditional SQL

Use "good old" SQL on your data with multiple levels of: JOIN, VIEW, GROUP BY, UNION, PRIMARY KEY, ANY, ALL, IN, ROLLUP(), CUBE(), GROUPING SETS(), CROSS APPLY, OUTER APPLY, WITH SELECT, and subqueries. The wiki lists supported SQL statements and keywords.

User-Defined Functions in your SQL

You can use all benefits of SQL and JavaScript together by defining your own custom functions. Just add new functions to the alasql.fn object:

alasql.fn.myfn = function (a, b) {
    return a * b + 1;
};
var res = alasql('SELECT myfn(a,b) FROM one');

You can also define your own aggregator functions (like your own SUM(...)). See more in the wiki

Compiled statements and functions

var ins = alasql.compile('INSERT INTO one VALUES (?,?)');
ins(1, 10);
ins(2, 20);

See more in the wiki

SELECT against your JavaScript data

Group your JavaScript array of objects by field and count number of records in each group:

var data = [
    {a: 1, b: 1, c: 1},
    {a: 1, b: 2, c: 1},
    {a: 1, b: 3, c: 1},
    {a: 2, b: 1, c: 1},
];
var res = alasql('SELECT a, COUNT(*) AS b FROM ? GROUP BY a', [data]);

See more ideas for creative data manipulation in the wiki

JavaScript Sugar

AlaSQL extends "good old" SQL to make it closer to JavaScript. The "sugar" includes:

• Write Json objects - {a:'1',b:@['1','2','3']}

• Access object properties - obj->property->subproperty

• Access object and arrays elements - obj->(a*1)
• Access JavaScript functions - obj->valueOf()
• Format query output with SELECT VALUE, ROW, COLUMN, MATRIX
• Output nested objects with INTO OBJECT() - converts arrow notation columns back to nested structure
• ES5 multiline SQL with var SQL = function(){/*SELECT 'MY MULTILINE SQL'*/} and pass instead of SQL string (will not work if you compress your code)

Extracting Nested Properties with INTO OBJECT()

When selecting nested properties using arrow notation (->), results are normally flattened with the arrow path as the key. Use INTO OBJECT() to restore the nested structure:

var data = [{name: 'Oslo', info: {country: 'Norway', population: 700000}}];

// Standard output (flattened)
alasql('SELECT name, info->country FROM ?', [data]);
// [{ "name": "Oslo", "info->country": "Norway" }]

// With INTO OBJECT() (nested)
alasql('SELECT name, info->country INTO OBJECT() FROM ?', [data]);
// [{ "name": "Oslo", "info": { "country": "Norway" } }]

Read and write Excel and raw data files

You can import from and export to CSV, TAB, TXT, and JSON files. File extensions can be omitted. Calls to files will always be asynchronous so multi-file queries should be chained:

var tabFile = 'mydata.tab';

alasql
    .promise([
        "SELECT * FROM txt('MyFile.log') WHERE [0] LIKE 'M%'", // parameter-less query
        ['SELECT * FROM tab(?) ORDER BY [1]', [tabFile]], // [query, array of params]
        "SELECT [3] AS city,[4] AS population FROM csv('./data/cities')",
        "SELECT * FROM json('../config/myJsonfile')",
    ])
    .then(function (results) {
        console.log(results);
    })
    .catch(console.error);

Read SQLite database files

AlaSQL can read (but not write) SQLite data files using SQL.js library:

<script src="https://github.com/AlaSQL/alasql/raw/v5.0.0/alasql.js"></script>
<script src="https://github.com/AlaSQL/alasql/raw/v5.0.0/sql.js"></script>
<script>
    alasql([
        'ATTACH SQLITE DATABASE Chinook("Chinook_Sqlite.sqlite")',
        'USE Chinook',
        'SELECT * FROM Genre',
    ]).then(function (res) {
        console.log('Genres:', res.pop());
    });
</script>

sql.js calls will always be asynchronous.

AlaSQL works in the console - CLI

The node module ships with an alasql command-line tool:

$ npm install -g alasql ## install the module globally

$ alasql -h ## shows usage information

$ alasql "SET @data = @[{a:'1',b:?},{a:'2',b:?}]; SELECT a, b FROM @data;" 10 20
[ 1, [ { a: 1, b: 10 }, { a: 2, b: 20 } ] ]

$ alasql "VALUE OF SELECT COUNT(*) AS abc FROM TXT('README.md') WHERE LENGTH([0]) > ?" 140
// Number of lines with more than 140 characters in README.md

More examples are included in the wiki

Features you might love

AlaSQL ♥ D3.js

AlaSQL plays nice with d3.js and gives you a convenient way to integrate a specific subset of your data with the visual powers of D3. See more about D3.js and AlaSQL in the wiki

AlaSQL ♥ Excel

AlaSQL can export data to both Excel 2003 (.xls) and Excel 2007 (.xlsx) formats with coloring of cells and other Excel formatting functions.

AlaSQL ♥ Meteor

Meteor is amazing. You can query directly on your Meteor collections with SQL - simple and easy. See more about Meteor and AlaSQL in the wiki

AlaSQL ♥ Angular.js

Angular is great. In addition to normal data manipulation, AlaSQL works like a charm for exporting your present scope to Excel. See more about Angular and AlaSQL in the wiki

AlaSQL ♥ Goog