Versions affected: All versions of DSP / ADM / ISA with Advanced View Builder functionality
If you use the Advanced View Builder and set the [DATABASE FOR VIEWS] and the [DATABASE FOR TABLES] to the same value (and click 'Build View'), then all of the views in that database will be dropped.
Please note the Online Help warning of this issue:
Never have the same value in Database for Views and Database for Tables. If this has already happened, restoring a backup of the affected database to a new name and then scripting the views out should work.