[Database class] Improved examples

[Paul S. Wang]

DB class,

Please revisit

http://dbdev.cs.kent.edu/database/notes/join.html

and see the improvements using subqueries.  Compare the
queries in this page to see their differences/similarities.

Paul
-- 
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 Paul S. Wang (王士弘)                      Email: pwang at cs.kent.edu            
 Dept. of Computer Science, Kent State U.   Tel: (330) 672-9051
 Kent, Ohio, USA 44242-0001                 http://www.cs.kent.edu/~pwang/ 
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