My Host-provider provided only 2 Mysql databases for me! I want to install 3 or more Drupal websites for each department in my university.

i.e. each website in subdomain1.domain.com, subdomain2.domain.com, etc. Each website should be independent with other as webmasters for each site will be different.

I tried out with sites/default/default.settings.php also but i got struck somewhere in coding there!

please help me in this regard! I'll make sure that Drupal has good Development community!
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M.Venkata Satish,
IT Administrator,
Vignan University