SharePoint Powershell Commands

To restore a site collection by using Windows PowerShell

1. Verify that you meet the following minimum requirements: See Add-SPShellAdmin. Additionally, verify that the user account performing this procedure has read permissions to the backup folder and is a member of the db_owner fixed database role on both the farm configuration database and the content database where the site collection is being restored.
2. On the Start menu, click All Programs.
3. Click Microsoft SharePoint 2010 Products.
4. Click SharePoint 2010 Management Shell.
5. At the Windows PowerShell command prompt (that is, PS C:\>), type the following command, and then press ENTER:
   Restore-SPSite -Identity <Site collection URL> -Path <Backup file> [-DatabaseServer <Database server name>] [-DatabaseName <Content database name>] [-HostHeader <Host header>] [-Force] [-GradualDelete] [-Verbose]
   If you want to restore the site collection to a specific content database, use the DatabaseServer and DatabaseName parameters to specify the content database. If you do not specify a content database, the site collection will be restored to a content database chosen by Microsoft SharePoint Server 2010.
   If you are restoring a host-named site collection, use the Identity parameter to specify the URL of the host-named site collection and use the HostHeader parameter to specify the URL of the Web application that will hold the host-named site collection.
   If you want to overwrite an existing site collection, use the Force parameter.

Example:
Restore-SPSite -Identity "http://eis" -Path "c:\backup\eis.bak" -Force