Update README.md

Author: lovasoa

README.md

@@ -19,59 +19,63 @@ A [full documentation](http://kripken.github.io/sql.js/documentation/#http://kri
 
 ## Usage
 
+By default, *sql.js* uses [wasm](https://developer.mozilla.org/en-US/docs/WebAssembly), and thus needs to load a .wasm file in addition to the javascript library. You can find this file in `./node_modules/sql.js/dist/sql-wasm.wasm` after installing sql.js from npm, and add it to your static assets. Alternatively, you can load the file from a CDN :
+
 ```javascript
-var initSqlJs = require('sql.js');
+const initSqlJs = require('sql.js');
 // or if you are in a browser:
 // var initSqlJs = window.initSqlJs;
 
-initSqlJs().then(SQL => {
-
-  // 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();
+const SQL = await initSqlJs({
+  // Required to load the wasm binary asynchronously. Of course, you can host it wherever you want
+  // You can omit locateFile completely when running in node
+  locateFile: file => `https://cdnjs.cloudflare.com/ajax/libs/sql.js/1.1.0/dist/${file}`
 });
 
+// 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();
 ```
 
 ## Demo