I know I can move one site collection to another web application (on a different database) by using backup and restore. But what if I have like 100 site collections I want to move out to another web app? Is there any way I can do it at one go? If yes, how? Thanks.

If you want to move all these seite collections and not copy, then consider detaching the databases form the source web application and attaching them to the destination web application. Detaching database = Central Administration => Manage Content database - select the web application - select the content database - check "Remove content database" ( will only detach the datbase form SharePoint and not remove form SQL) Attach database = Central Administration => Manage Content database - select the web application - select Add content database - specify name of content database previously removed form original web application You can also consider doing this using the SharePoint 2010 Management Shell (powershell) using the commands Remove-SPContentDatabase and Mount-SPContentDatabase Dirk Van den Berghe