Can SharePoint 2010 search in an external customer database (not BCS)?

Can SharePoint 2010 search in an external customer database (not BCS) ? Such as a norma开发者_高级运维l sql database?

Is that possible ?

Out of the box content sources types do not include a raw database (not via external content types/bcs)

http://technet.microsoft.com/en-us/library/cc262866%28office.12%29.aspx

But it should be possible, if you implement your own protocol handler

http://msdn.microsoft.com/en-us/library/aa981260%28v=office.12%29.aspx

http://msdn.microsoft.com/en-us/library/bb266531%28v=vs.85%29.aspx