> Can any one please tell me some site for using ajax
> with database connectivity.
Well my friend AJAX is nothing but simple client side Java-scripting..
One cannot access db using it...rather it would go in the traditional way of calling web-tier-->Biz layer-->DA layer & send out an XML/JSON/TEXT response to the client and then depending on the XML/JSON/TEXT reponse the client parses the XML/JSON/TEXT and updates its view accordingly.
However,for a starter i'd recommend to go with the below links
http://www.oracle.com/technology/pub/articles/vohra-ajax.html
http://java.sun.com/developer/technicalArticles/J2EE/AJAX/
http://courses.coreservlets.com/Course-Materials/ajax.html
https://bpcatalog.dev.java.net/nonav/solutions.html
http://courses.coreservlets.com/Course-Materials/pdf/ajax/Ajax-Basics.pdf
http://www.roseindia.net/ajax/ajax-tutorials.shtml
http://www.roseindia.net/ajax/ajax-examples.shtml
Hope that might help :)
REGARDS,
RaHuL