单项选择题
What is necessary for your query on an existing view to execute successfully?（）
A. The underlying tables must have data. B. You need SELECT privileges on the view. C. The underlying tables must be in the same schema. D. You need SELECT privileges only on the underlying tables.
多项选择题 Which two statements accurately describe a role? （）
单项选择题 Examine the structure of the EMPLOYEES and NEW_EMPLOYEES tables: Which UPDATE statement is valid?（）
单项选择题 In which case would you use a FULL OUTER JOIN?（）
