drop_database_stmt ::=
	'DROP' 'DATABASE' database_name 'CASCADE'
	| 'DROP' 'DATABASE' database_name 'RESTRICT'
	| 'DROP' 'DATABASE' database_name 
	| 'DROP' 'DATABASE' 'IF' 'EXISTS' database_name 'CASCADE'
	| 'DROP' 'DATABASE' 'IF' 'EXISTS' database_name 'RESTRICT'
	| 'DROP' 'DATABASE' 'IF' 'EXISTS' database_name 
