多项选择题
A. Constraint names must start with SYS_C
B. All constraints must be defines at the column level
C. Constraints can be created after the table is created
D. Constraints can be created at the same time the table is created
E. Information about constraints is found in the VIEW_CONSTRAINTS dictionary view
单项选择题 The CUSTOMERS table has these columns: Which statement finds the rows in the CUSTOMERS table that do not have a postal code?（）
单项选择题 You are granted the CREATE VIEW privilege. What does this allow you to do?（）
多项选择题 Evaluate the SQL statement DROP TABLE DEPT: Which four statements are true of the SQL statement?（）