单项选择题
For which action can you use the TO_DATE function? （）
A. Convert any date literal to a date B. Convert any numeric literal to a date C. Convert any character literal to a date D. Convert any date to a character literal E. Format '10-JAN-99' to 'January 10 1999'
单项选择题 What is true regarding subqueries?（）
单项选择题 What is true about sequences? （）
单项选择题 Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2 (25) LAST_NAME VARCHAR2 (25) HIRE_DATE DATE Which UPDATE statement is valid? （）
