Advantage : You get all the words of many of the articles right
here on your screen. You don't have to go to the library or
make a special request to get the articles.
Disadvantage: These databases include a relatively small
subset of the journals published in nursing. And not all of
the articles will be provided full-text on your screen, even for
this smaller subset of journals.

Advantage: These databases provide exhaustive coverage of
the subject area. Especially in medicine, you want to make
sure that you have not overlooked an important study when making
evidence-based decisions.
Disadvantage: They do not provide the full-text of the
article. They may link to the full-text in another (smaller)
database, but many of the articles will have to be ordered or
tracked down in the library's print subscriptions.