For the impatients, try the demo here: http://kripken.github.io/sql.js/GUI/
sql.js is a port of SQLite to JavaScript, by compiling the SQLite C code with Emscripten. no C bindings or node-gyp compilation here.
SQLite is public domain, sql.js is MIT licensed.
A full documentation generated from comments inside the source code, is available.
var sql = require('sql.js');
// or sql = window.SQL if you are in a browser
// in a browser, use the following callback before
// performing any action, since it is async
sql.onRuntimeInitialized = function() { ... }
// Create a database
var db = new sql.Database();
// NOTE: You can also use new sql.Database(data) where
// data is an Uint8Array representing an SQLite database file
// Execute some sql
sqlstr = "CREATE TABLE hello (a int, b char);";
sqlstr += "INSERT INTO hello VALUES (0, 'hello');"
sqlstr += "INSERT INTO hello VALUES (1, 'world');"
db.run(sqlstr); // Run the query without returning anything
var res = db.exec("SELECT * FROM hello");
/*
[
{columns:['a','b'], values:[[0,'hello'],[1,'world']]}
]
*/
// Prepare an sql statement
var stmt = db.prepare("SELECT * FROM hello WHERE a=:aval AND b=:bval");
// Bind values to the parameters and fetch the results of the query
var result = stmt.getAsObject({':aval' : 1, ':bval' : 'world'});
console.log(result); // Will print {a:1, b:'world'}
// Bind other values
stmt.bind([0, 'hello']);
while (stmt.step()) console.log(stmt.get()); // Will print [0, 'hello']
// You can also use javascript functions inside your SQL code
// Create the js function you need
function add(a, b) {return a+b;}
// Specifies the SQL function's name, the number of it's arguments, and the js function to use
db.create_function("add_js", add);
// Run a query in which the function is used
db.run("INSERT INTO hello VALUES (add_js(7, 3), add_js('Hello ', 'world'));"); // Inserts 10 and 'Hello world'
// free the memory used by the statement
stmt.free();
// You can not use your statement anymore once it has been freed.
// But not freeing your statements causes memory leaks. You don't want that.
// Export the database to an Uint8Array containing the SQLite database file
var binaryArray = db.export();
There is an online demo available here : http://kripken.github.io/sql.js/GUI
The test files provide up to date example of the use of the api.
<script src='js/sql.js'></script>
<script>
SQL.onRuntimeInitialized = function() {
//Create the database
var db = new SQL.Database();
// Run a query without reading the results
db.run("CREATE TABLE test (col1, col2);");
// Insert two rows: (1,111) and (2,222)
db.run("INSERT INTO test VALUES (?,?), (?,?)", [1,111,2,222]);
// Prepare a statement
var stmt = db.prepare("SELECT * FROM test WHERE col1 BETWEEN $start AND $end");
stmt.getAsObject({$start:1, $end:1}); // {col1:1, col2:111}
// Bind new values
stmt.bind({$start:1, $end:2});
while(stmt.step()) { //
var row = stmt.getAsObject();
// [...] do something with the row of result
}
}
</script>
SQL.Database
constructor takes an array of integer representing a database file as an optional parameter.
The following code uses an HTML input as the source for loading a database:
dbFileElm.onchange = function() {
var f = dbFileElm.files[0];
var r = new FileReader();
r.onload = function() {
var Uints = new Uint8Array(r.result);
db = new SQL.Database(Uints);
}
r.readAsArrayBuffer(f);
}
See : http://kripken.github.io/sql.js/GUI/gui.js
var xhr = new XMLHttpRequest();
xhr.open('GET', '/path/to/database.sqlite', true);
xhr.responseType = 'arraybuffer';
xhr.onload = function(e) {
var uInt8Array = new Uint8Array(this.response);
var db = new SQL.Database(uInt8Array);
var contents = db.exec("SELECT * FROM my_table");
// contents is now [{columns:['col1','col2',...], values:[[first row], [second row], ...]}]
};
xhr.send();
See: https://github.com/kripken/sql.js/wiki/Load-a-database-from-the-server
sql.js
is hosted on npm. To install it, you can simply run npm install sql.js
.
Alternatively, you can simply download the file sql.js
, from the download link below.
var fs = require('fs');
var SQL = require('sql.js');
var filebuffer = fs.readFileSync('test.sqlite');
// Load the db
var db = new SQL.Database(filebuffer);
You need to convert the result of db.export
to a buffer
var fs = require("fs");
// [...] (create the database)
var data = db.export();
var buffer = new Buffer(data);
fs.writeFileSync("filename.sqlite", buffer);
See : https://github.com/kripken/sql.js/blob/master/test/test_node_file.js
If you don't want to run CPU-intensive SQL queries in your main application thread, you can use the more limited WebWorker API.
You will need to download worker.sql.js
Example:
<script>
var worker = new Worker("js/worker.sql.js"); // You can find worker.sql.js in this repo
worker.onmessage = function() {
console.log("Database opened");
worker.onmessage = function(event){
console.log(event.data); // The result of the query
};
worker.postMessage({
id: 2,
action: 'exec',
sql: 'SELECT * FROM test'
});
};
worker.onerror = function(e) {console.log("Worker error: ", e)};
worker.postMessage({
id:1,
action:'open',
buffer:buf, /*Optional. An ArrayBuffer representing an SQLite Database file*/
});
</script>
See : https://github.com/kripken/sql.js/blob/master/test/test_worker.js
- You can download
sql.js
here : https://raw.githubusercontent.com/kripken/sql.js/master/js/sql.js - And the Web Worker version: https://raw.githubusercontent.com/kripken/sql.js/master/js/worker.sql.js
- You can find a non minified or optimized version for debugging,
sql-debug.js
here : https://raw.githubusercontent.com/kripken/sql.js/master/js/sql-debug.js - If you see the message,
Cannot enlarge memory arrays
, try this version,sql-memory-growth.js
here : https://raw.githubusercontent.com/kripken/sql.js/master/js/sql-memory-growth.js