My requirement is to rename a site URL, so I took a STSADM backup, then I went to restore using the new URL. When I ran the restore with the new URL, It resulted in the below error:
“No content databases are available for this operation. Create a content database, and then try the operation again. To create a content database, click Content databases on the Application Management page, select the Web application to use, and then click Add a content database”
The problem is: The GUID of the new site I’m trying to create is the same as an existing site.
Delete the old site collection and then run the stsadm -o restore again!
Microsoft KB article addresses this issue: http://support.microsoft.com/kb/926321