Database settings are retained if you deactivate the plugin.
Database settings are removed if you uninstall the plugin...
If you select the application shown in the not below screen shot this is what you'll see..
Upload seeing red. php to the wp-content plugins directory.
Activate the plugin through 'Plugins in WordPress.
I work with category of people who are to WordPress and they are just of Screen Options tab.
It's of these them that you need usually that WP users are aware of and that is mystery to noobs...
Browse the code recheck out SVN repository or subscribe to the development log RSS....
Database settings are retained in the event of deactivation.
Database settings are removed in the event of uninstallation..
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