# sql.js: Using SQLite Databases with Firefox OS Apps
Developers coming from platforms like Android might seek for support for SQLite-like functionality in Firefox OS as well, but sadly the WebSQL specification was dropped and Firefox OS doesn’t have native SQLite support. However, you can still use SQLite through a [JavaScript](https://so.csdn.net/so/search?q=JavaScript&spm=1001.2101.3001.7020) library, [sql.js](https://github.com/kripken/sql.js/), which is SQLite compiled to JavaScript!
Warning: This approach might have performance penalties
### Getting started with sql.js
Let’s first start with a blank fresh index.html with a basic template. Download sql.js from the link above (impatient ones can just[click here](https://github.com/kripken/sql.js/blob/master/js/sql.js?raw=true)) and attach it as a script to your index.html. Which should look something like this.
index.html
```typescript
...
```
Now we have SQLite functionality available to our app! Now to be able to execute our own code, let’s add our very own JavaScript file to our app, I am willing to name it dbHelper.js, you can name it as you like, and again attach to index.html.
index.html
```typescript
...
```
We are all set to go, let’s dive in!
### Creating the Database
Before we get started with populating tables with data to save the world from meteoroids, we need to create a database for those tables to be in.
dbHelper.js
```typescript
var db = new SQL.Database();
```
And there you have it, you have an SQLite database ready to interact with!
### Executing Queries
Now that we have a database, we can execute some queries for populating data, making tables or anything SQLite is capable [of.*db.run*](http://of.db.run)\*(query)\*is the way to execute queries on your database if you don’t need any returns from the query.
dbHelper.js
```javascript
var le_query = "CREATE TABLE Meteoroids (id int, name char, distance int);";db.run(le_query);
```
Or, if you love one-liners,
dbHelper.js
```javascript
db.run("CREATE TABLE Meteoroids (id int, name char, distance int);");
```
However, if you are expecting the query to return something, instead you should use*db.exec(query)*.
dbHelper.js
```javascript
var result = db.exec("SELECT * from Meteoroids;");
```
### Saving the database
You app might need to (and probably will need to) save that database somewhere for future use and you have a variety of choices to choose from. Before going anywhere else, exporting our database into an *Uint8Array* is probably a good thing.
```typescript
var binaryArray = db.export();
```
Now we can make a Blob out of it to save it as a file on the [device storage](https://developer.mozilla.org/en-US/docs/Web/API/Device_Storage_API), or we can use localStorage/IndexedDB (or [localForage.js](http://mozilla.github.io/localForage/), a fantastic library to handle complications for us).
```typescript
var sqlFile = new Blob(binaryArray);
```
### Opening the database from a Uint8Array
Again, after saving the database, opening it up will probably be required sometimes in the future. First, retrieve your**Uint8Array**from wherever and no matter how you stored it.
```typescript
var binaryarray = this_is_sparta(); // somehow you get the Uint8Array
```
And, getting our Database ready is as simple as,
```typescript
var db = SQL.Database(binaryarray);
```
And now that we are done with the very basics of sql.js, we can explore a bit more of what this library has to offer. Reading the [documentation](http://kripken.github.io/sql.js/documentation/) and [example code](https://github.com/kripken/sql.js/blob/master/README.md) would now make some sense to you.