1Z0-007章节练习(2020.04.25)

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
多项选择题
Which two statements about subqueries are true? （）
A. A subquery should retrieve only one row.
B. A subquery can retrieve zero or more rows.
C. A subquery can be used only in SQL query statements.
D. Subqueries CANNOT be nested by more than two levels.
E. A subquery CANNOT be used in an SQL query statement that uses group functions.
F. When a subquery is used with an inequality comparison operator in the outer SQL statement, the column list in the SELECT clause of the subquery should contain only one column.
单项选择题
You created a view called EMP_DEPT_VU that contains three columns from the EMPLOYEES and DEPARTMENTS tables:EMPLOYEE_ID, EMPLOYEE_NAME AND DEPARTMENT_NAME.The DEPARTMENT_ID column of the EMPLOYEES table is the foreign key to the primary key DEPARTMENT_ID column of the DEPARTMENTS table.You want to modify the view by adding a fourth column, MANAGER_ID of NUMBER data type from the EMPLOYEES tables.How can you accomplish this task?（）
A. ALTER VIEW EMP_dept_vu (ADD manger_id NUMBER);
B. MODIFY VIEW EMP_dept_vu (ADD manger_id NUMBER);
C. ALTER VIEW emp_dept_vu AS SELECT employee_id, employee_name, department_name, manager_id FROM employee e, departments d WHERE e.department _ id = d.department_id;
D. MODIFY VIEW emp_dept_vu AS SELECT employee_id, employee_name, department_name, manager_id FROM employees e, departments d WHERE e.department _ id = d.department_id;
E. CREATE OR REPLACE VIEW emp_dept_vu AS SELECT employee_id, employee_name, department_name, manager_id FROM employees e, departments d WHERE e.department _ id = d.department_id;
F. You must remove the existing view first, and then run the CREATE VIEW command with a new column list to modify a view.
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.
单项选择题
Examine the structure if the EMPLOYEES and NEW EMPLOYEES tables:Which MERGE statement is valid?（）
A.
B.
C.
D.
多项选择题
From SQL*Plus, you issue this SELECT statement:You use this statement to retrieve data from a data table for（）。
A. Updating
B. Viewing
C. Deleting
D. Inserting
E. Truncating
单项选择题
Evaluate this SQL statement:SELECT ename, sal, 12* sal+100 FROM emp;The SAL column stores the monthly salary of the employee. Which change must be made to the above syntax to calculate the annual compensation as "monthly salary plus a monthly bonus of $100, multiplied by 12"?（）
A. No change is required to achieve the desired results.
B. SELECT ename, sal, 12* (sal+100) FROM emp;
C. SELECT ename, sal, (12* sal)+100 FROM emp;
D. SELECT ename, sal +100,*12 FROM emp;
多项选择题
Which three statements about subqueries are true? （）
A. A main query can have more than one subquery.
B. A subquery can have more than one main query.
C. The subquery and main query must retrieve data from the same table.
D. The subquery and main query can retrieve data from different tables.
E. Only one column or expression can be compared between the subquery and main query.
F. Multiple columns or expression can be compared between the subquery and main query.
单项选择题
You need to perform certain data manipulation operations through a view called EMP_DEPT_VU, which you previously created. You want to look at the definition of the view (the SELECT statement on which the view was created.) How do you obtain the definition of the view?（）
A.Use the DESCRIBE command on the EMP_DEPT_VU view.
B.Use the DEFINE VIEW command on the EMP_DEPT_VU view.
C.Use the DESCRIBE VIEW command on the EMP_DEPT_VU view.
D.Query the USER_VIEWS data dictionary view to search for the EMP_DEPT_VU view.
E.Query the USER_SOURCE data dictionary view to search for the EMP_DEPT_VU view.
F.Query the USER_OBJECTS data dictionary view to search for the EMP_DEPT_VU view.
多项选择题
Which two statements complete a transaction? （）
A.DELETE employees;
B.DESCRIBE employees;
C.ROLLBACK TO SAVEPOINT C;
D.GRANT SELECT ON employees TO SCOTT;
E.ALTER TABLE employees SET UNUSED COLUMN sal;
F.SELECT MAX(sal) FROM employees WHERE department_id = 20;