Alasql.js - pure JavaScript client-side in-memory fast SQL-database

Version: 0.0.14.3 Date: November 9, 2014 Changelog

Alasql - 'à la SQL' - is a lightweight client-side in-memory SQL database designed to work in browser and Node.js.

• Alasql was written with pure JavaScript and does not use browser WebSQL database.
• Alasql is fully functional compact sql server with JOINs, GROUPs, UNIONs, ANY, ALL, IN, subqueries and very limited transactions support.
• Alasql supports ROLLUP(), CUBE() and GROUPING SETS() functions
• Alasql works with all modern versions of browsers (Chrome, Firefox, IE, Safari), Node.js, and mobile iOS and Android.
• Alasql is fast, because it uses some optimization methods.

Check Alasql vs other JavaScript databases:

• Alabase vs. WebSQL
• Alabase vs. SQL.js

Warning: Alasql project is very young and still in active development phase, therefore it may has some bugs. Please, wait a little bit before start to use it in production. I am going to add more tests and clean the code before relaese more stable version 0.1.0 in the mid of November.

Examples

Try Alasql in Fiddle: sample 1, sample 2, sample 3

Other examples:

• Sandbox
• Sieve of Eratosthenes

Installation

In browser

Include file: alasql.js to the page.

  <script src="alasql.js"></script>  
  <script>
    alasql.exec("CREATE TABLE test (language INT, hello STRING)");
    alasql.exec("INSERT INTO test VALUES (1,'Hello!')");
    alasql.exec("INSERT INTO test VALUES (2,'Aloha!')");
    alasql.exec("INSERT INTO test VALUES (3,'Bonjour!')");
    console.table(alasql.exec("SELECT * FROM test WHERE language > 1"));
  </script>

You can use alasql.js with define()/require() functions in browser as well, because it supports AMD and UMD.

In Node.js

Use the following command for installation:

    npm install alasql

Then require alasql.js file:

    var alasql = require('alasql');

    var db = new alasql.Database();
    
    db.exec("CREATE TABLE test (one INT, two INT)");
    db.tables.test.data = [   // You can mix SQL and JavaScript
        {one:3,two:4},
        {one:5,two:6},
    ];
    var res = db.exec("SELECT * FROM test ORDER BY two DESC");
    console.log(res[0].one);

Supported SQL statements

• SELECT fields FROM tableid1 JOIN tableid2 ON oncond WHERE cond GROUP BY v1,v2 HAVING cond ORDER BY a,b, LIMIT number OFFSET number
• INSERT INTO table [ (field1, field2) ] VALUES (value1, value2), (value3, value4), ...
• INSERT INTO table SELECT subquery
• UPDATE table SET field = value1, field = value2 WHERE condition
• DELETE FROM table WHERE condition
• CREATE TABLE [IF NOT EXISTS] table
• DROP TABLE [IF EXISTS] table

SELECT statement

Now Alasql.js supports following subset of SELECT syntax:

• SELECT column1, column2 AS alias3, FUNCTION(field4+field5) AS alias6, SUM(expression7) AS alias8, , table2.
• FROM table1, table2, (SELECT * FROM table3) alias
• LEFT / RIGHT / INNER / OUTER / ANTI / SEMI / CROSS JOIN table2 ON condition / USING columns
• WHERE condition
• GROUP BY column1, column2, ROLLUP(a,b), CUBE(c,d,e), GROUPING SETS(g,h)
• HAVING condition
• ORDER BY column1, column2 DESC,
• LIMIT number [OFFSET number]
• UNION / UNION ALL select / INTERSECT / EXCEPT

Operators

• +, -, *, /, %, AND, OR, NOT, BETWEEN, NOT BETWEEN, EXISTS (Subquery), > ALL (subquery/array), > ANY/SOME (subquery / array), [NOT] IN (subquery / array), LIKE

Functions

• ABS(), IIF(), IFNULL(), INSTR(), LOWER(), UPPER(), LCASE(), UCASE(), LEN(), LENGTH()

Aggregators

• SUM()
• COUNT()
• MIN()
• MAX()
• FIRST()
• LAST()
• Sorry, AVG still does not work

GROUP BY Grouping functions

• ROLLUP()
• CUBE()
• GROUPING SETS()

User-defined JavaScript functions

You can use all benefits of SQL and JavaScript togeather by defining user functions. Just add new functions to alasql.userlib object:

        alasql.userlib.DOUBLE = function(x){return x*2};        
        alasql.userlib.SUM10 = function(x,y) { return x+y*10; }
        db.exec('SELECT a, DOUBLE(a) AS b, SUM10(a,b) FROM test1');

alasql

alasql is a main variable of module. You can use it immediatly as default database

In browser:

    <script src="alasql.js"></script>
    <script>
        alasql.exec('CREATE TABLE one (two INT)');
    </script>

or in Node.js:

    var alasql = require('alasql');
    alasql.exec('CREATE TABLE one (two INT)');

Another approach is to create new database:

    var mybase = new alasql Database();
    mybase.exec('CREATE TABLE one (two INT)');

You can give a name to database and then access it from alasql:

    var mybase = new alasql Database('mybase');
    console.log(alasql.databases.mybase);

Each database can be used with the following methods:

• vat db = new alasql.Database() - create new alasql-database
• var res = db.exec("sql-statement") - executes SELECT query and returns array of objects

Usually, alasql.js works synchronously, but you can use callback.

    db.exec('SELECT * FROM test', function(res){
        console.log(res);
    });

or you can use aexec() - promised version of exec (in this case you need to install es6-promise module for Node.js) (this feature is experimental and may be removed in a future to reduce dependices):

    db.aexec('SELECT * FROM test').then(function(res){
        console.log(res);
    });

You can use compile statements:

    var insert = db.compile('INSERT INTO one (1,2)');
    insert();

You can use parameters in compiled statements:

    var insert1 = db.compile('INSERT INTO one (?,?)');
    var insert2 = db.compile('INSERT INTO one ($a,$b)');
    var insert3 = db.compile('INSERT INTO one (:a,:b)');

    insert1([1,2]);
    insert2({a:1,b:2});
    insert3({a:3,b:4});

    db.exec('INSERT INTO one (?,?)',[5,6]);

Transactions

There is a limited support of transactions (with tx.rollback() and tx.commit() functions):

    db = new alasql.Database("mydb");
    db.transaction(function(tx) {
        tx.exec('SELECT COUNT(*) FROM students');
        tx.rollback();
    });     

SQL to JavaScript parser and compiler

You can use Alasql to parse to AST and compile SQL statements:

    // Parse to AST
    var ast = alasql.parse("SELECT * FROM one");

    // Compile to JavaScript function with or without parameters
    var statement = alasql.compile("SELECT * FROM one WHERE a > ? AND b < ?");
    statement([1,5]);

Alasql uses wonderful Jison parser to produce AST-tree.

Performance

According the preliminary performance tests alasql.js is faster than sql.js in 5 to 10 times on more than 1000 records tables, and 2 to 3 times to WebSQL on different queries.

Alasql has four different optimization algorithm:

• Caching of compiled queries
• Joins: Preindexation of joined table
• Joins: Prefiltering of WHERE expressions

Now optimization algorithm has some limitations and therefore "table1 JOIN table2 USING column1, column2" is faster than "table1 JOIN table2 ON table1.column1 = table2.column1 AND table1.column2 = table2.column2 ", but with one column it is ok.

Limitations

It is Ok with select for 1000000 records or 2 join two tables by 10000 records in each.

Tests

I use mocha for tests. Run mocha from command line:

    mocha

or run test/main.html in browser.

Known Bugs

1. Negative numbers (uniminus) are not implemented yet
2. Dates sorting and comparing
3. Semicolon with multiple statements
4. ORDER BY clause on three or more UNIONS
5. AVG() does not work
6. There are many of others. Please, give me a chance to fix them. Thank you!

Future Plans

Read my to do page

Similar projects (SQL database, MDX/OLAP on JavaScript)

SQL-database:

• sql.js - port of SQLike to JavaScript
• SequelSphere - commercial SQL-database
• Datamanip
• jsonQ.js
• SQittle
• SQLinJS
• jQuery-SQL-Emulator

LINQ realizations:

• SQLike -
• JSLINQ
• JavaScriptSQL
• TrimQuery
• jlinq
• jSQL

Other:

• dom-storage-query-language
• kombai-js

JavaScript databases:

• SearchJS
• TaffyDB
• River
• CrossFilter
• js-hypercube
• cubico
• SimpleMemolap

Other

• Press about Alasql

Credits

Many thanks to Andrew Kent for his SQL Parser and other people for useful tools, which made our work much easier.

License

(c) 2014, Andrey Gershun (agershun@gmail.com), MIT licence information