>rake db:drop
Couldn't drop db/development.sqlite3 : #<Errno::EACCES: Permission denied - db/development.sqlite3>

maybe you run script/console and didn't exit.

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Liu Lantao
College of Information Science and Technology, Beijing Normal University
EMAIL: liulantao ( at ) gmail ( dot ) com ;
WEBSITE: http://www.liulantao.com/ .
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