{% include anchor.html title="Create a database" hash="create_database" %}

{% highlight js %}
new PouchDB([name], [options])
{% endhighlight %}

This method creates a database or opens an existing one. If you use a URL like `'http://domain.com/dbname'`, then PouchDB will work as a client to an online CouchDB instance.  Otherwise it will create a local database using [whatever backend is present](/adapters.html).

### Options

* `name`: You can omit the `name` argument and specify it via `options` instead. Note that the name is required.

**Options for local databases:**

* `auto_compaction`: This turns on auto compaction, which means `compact()` is called after every change to the database. Defaults to `false`.
* `adapter`: One of `'idb'`, `'leveldb'`, `'websql'`, or `'http'`. If unspecified, PouchDB will infer this automatically, preferring IndexedDB to WebSQL in browsers that support both (i.e. Chrome, Opera and Android 4.4+).

**Options for remote databases:**

* `ajax`: (Remote databases only.) Ajax requester options. For instance, passing in the options `{ajax: {timeout: 10000}}` will allow you to set the max timeout for an HTTP request. These are passed ver batim to [request][] (in Node.js) or  [a request shim](https://github.com/pouchdb/pouchdb/blob/master/lib/deps/request-browser.js) (in the browser), with the exception of:
* `ajax.cache`: Appends a random string to the end of all HTTP GET requests to avoid them being cached on IE. Set this to `true` to prevent this happening.
* `ajax.headers`: The `ajax.headers` option allows you to customise headers that are sent to the remote HTTP Server.
* `auth.username` + `auth.password`: You can specify HTTP auth parameters either by using a database with a name in the form `http://user:pass@host/name` or via the `auth.username` + `auth.password` options.
  
**WebSQL-only options:**

* `size`: amount in MB to request for storage, which you will need if you are storing >5MB in order to avoid storage limit errors on iOS/Safari. Details [here](/errors.html#not_enough_space).

**SQLite Plugin-only options:**

* `location`: where to store data on iOS, which may affect iTunes/iCloud backup, and thus whether or not your app gets rejected by Apple. See [SQLite Plugin documentation](https://github.com/brodysoft/Cordova-SQLitePlugin/#opening-a-database) and [iOS data storage guidelines](https://developer.apple.com/icloud/documentation/data-storage/index.html).
* `createFromLocation`: use a pre-populated database, so you can package it with your app and users don't have to wait for it to load. See the [SQLite Plugin documentation](https://github.com/brodysoft/Cordova-SQLitePlugin/#pre-populated-database).
* `androidDatabaseImplementation`: `1` to use the new `sqlite4java` implementation, `2` to use the older version based on the native Android APIs. Defaults to `1`. See the [SQLite Plugin documentation](https://github.com/litehelpers/Cordova-sqlite-storage#android-sqlite-implementation).

**Notes:**

1. In IndexedDB and WebSQL, PouchDB will use `_pouch_` to prefix the internal database names. Do not manually create databases with the same prefix.
2. When acting as a client on Node, any other options given will be passed to [request][].
3. When using the `'leveldb'` adapter (the default on Node), any other options given will be passed to [levelup][]. The storage layer of leveldb can be replaced by passing a level backend factory (such as [MemDOWN][]) as `options.db`. The rest of the supported options are [documented here][levelup_options].

[request]: https://github.com/mikeal/request
[levelup]: https://github.com/rvagg/node-levelup
[MemDOWN]: https://github.com/rvagg/memdown
[levelup_options]: https://github.com/rvagg/node-levelup/#options

#### Example Usage:
{% highlight js %}
var db = new PouchDB('dbname');
// or
var db = new PouchDB('http://localhost:5984/dbname');
{% endhighlight %}

Create a WebSQL-only Pouch (e.g. when using the [SQLite Plugin][] for Cordova/PhoneGap):

[sqlite plugin]: https://github.com/brodysoft/Cordova-SQLitePlugin

{% highlight js %}
var db = new PouchDB('dbname', {adapter : 'websql'});
{% endhighlight %}

Create an in-memory Pouch (in Node):

{% highlight js %}
var db = new PouchDB('dbname', {db : require('memdown')});
{% endhighlight %}

Create a remote PouchDB with special Ajax options:

{% highlight js %}
var db = new PouchDB('http://example.com/dbname', {
  ajax: {
    cache: false,
    timeout: 10000,
    headers: {
      'X-Some-Special-Header': 'foo'
    },
  },
  auth: {
    username: 'mysecretusername',
    password: 'mysecretpassword'
  }
});
{% endhighlight %}

For more info, check out [adapters](/adapters.html).