单项选择题
A.The DESCRIBE DEPT statement displays the structure of the DEPT table.
B.The ROLLBACK statement frees the storage space occupied by the DEPT table.
C.The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.
D.The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.
多项选择题 Which are DML statements?（）
单项选择题 Evaluate the SQL statement:SELECT ROUND(45.953, -1), TRUNC(45.936, 2)FROM dual;Which values are displayed?（）
多项选择题 Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) Which three statements insert a row into the table? （）