多项选择题
Which three statements about subqueries are true?（）
A. A single row subquery can retrieve only one column and one row.
B. A single row subquery can retrieve only one row but many columns.
C. A multiple row subquery can retrieve multiple rows and multiple columns.
D. A multiple row subquery can be compared by using the “>” operator.
E. A single row subquery can use the IN operator.
F. A multiple row subquery can use the “=” operator.
相关考题
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单项选择题
Which SQL statement returns a numeric value?（）
A. SELECT ADD_MONTHS(MAX(hire_Date), 6) FROM EMP;
B. SELECT ROUND(hire_date) FROM EMP;
C. SELECT sysdate-hire_date FROM EMP;
D. SELECT TO_NUMBER(hire_date + 7) FROM EMP; -
多项选择题
When should you create a role?（）
A. To simplify the process of creating new users using the CREATE USER xxx IDENTIFIED by yyy statement.
B. To grant a group of relate privileges to a user.
C. When the number of people using the database is very high.
D. To simplify the process of granting and revoking privileges.
E. To simplify profile maintenance for a user who is constantly traveling. -
单项选择题
Which clause would you use in a SELECT statement to limit the display to those employees whose salary is greater then 5000?（）
A. ORDER BY SALARY > 5000
B. GROUP BY SALARY > 5000
C. HAVING SALARY > 5000
D. WHERE SALARY > 5000
