SharePoint: Adding content database to Webapplication

1. Verify that the user account that is being used to perform this operation is a member of the Farm Administrators SharePoint group. If you are using Windows authentication to connect to SQL Server, the user account must also be a member the SQL Server dbcreator fixed server role on the SQL Server instance where the database will be created. If you are using SQL authentication to connect to SQL Server, the SQL authentication account that you specify when you create the content database must have dbcreator permission on the SQL Server instance where the database will be created.
   
2. On the SharePoint Central Administration Web site, click Application Management.
   
3. In the Databases section, click Manage content databases.
   
4. On the Manage Content Databases page, click Add a content database.
   
5. On the Add Content Database page:
   
   1. Specify a Web application for the new database.
      
   2. Specify a database server to host the new database.
      
   3. Specify the authentication method that the new database will use and supply an account name and password, if they are necessary.
   4. Specify the name of the failover database server, if one exists.
      
   5. Specify the number of top-level sites that can be created before a warning is issued. By default, this is 9,000.
      
   6. Specify the total number of top-level sites that can be created in the database. By default, this is 15,000.
   7. Click OK.