[xwiki-users] Xwiki / accessing external SQL database / How to use SQL plugin ?

Hi, We are looking for the best way to access an external SQL database using velocity exclusively (because we can't write a macro using groovy language). So, we installed and tried to use this plugin : http://extensions.xwiki.org/xwiki/bin/view/Extension/SQL+Plugin. The plugin is properly installed. Now we are unsure how to use it : there is no mention of the user which is used to connect to the database, do we have to to configure a JNDI ? How ? As a side question, what is you guys your preferred method to program xwiki pages with external database access ? Thanks -- Martin