The EMP table contains these columns:L...

单项选择题 The EMP table contains these columns:
LAST_NAME VARCHAR2 (25)
SALARY NUMBER (6,2)
DEPARTMENT_ID NUMBER (6)
You need to display the employees who have not been assigned to any department. You write the SELECT statement:
SELECT LAST_NAME, SALARY, DEPARTMENT_ID
FROM EMP
WHERE DEPARTMENT_ID = NULL;
What is true about this SQL statement ?（）

A.The SQL statement displays the desired results.
B.The column in the WHERE clause should be changed to display the desired results.
C.The operator in the WHERE clause should be changed to display the desired results.
D.The WHERE clause should be changed to use an outer join to display the desired results.

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1.单项选择题 Click the Exhibit button to examine the structures of the EMPLOYEES, DEPARTMENTS, and TAX tables.
For which situation would you use a nonequijoin query?（）

A.to find the tax percentage for each of the employees
B.to list the name, job_id, and manager name for all the employees
C.to find the name, salary, and the department name of employees who are not working with Smith
D.to find the number of employees working for the Administrative department and earning less than 4000
E.to display name, salary, manager ID, and department name of all the employees, even if the employees do not have a department ID assigned

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2.单项选择题 Examine the description of the CUSTOMERS table:
CUSTOMER_ID NUMBER(4) NOT NULL
CUSTOMER_NAME VARCHAR2(100) NOT NULL
STREET_ADDRESS VARCHAR2(150)
CITY_ADDRESS VARCHAR2(50)
STATE_ADDRESS VARCHAR2(50)
PROVINCE_ADDRESS VARCHAR2(50)
COUNTRY_ADDRESS VARCHAR2(50)
POSTAL_CODE VARCHAR2(12)
CUSTOMER_PHONE VARCHAR2(20)
The CUSTOMER_ID column is the primary key for the table.
Which statement returns the city address and the number of customers in the cities Los Angeles or San Francisco?（）

A.SELECT city_address, COUNT(*) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco');
B.SELECT city_address, COUNT(*) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco') GROUP BY city_address;
C.SELECT city_address, COUNT(customer_id) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco') GROUP BY city_address, customer_id;
D.SELECT city_address, COUNT(customer_id) FROM customers GROUP BY city_address IN ('Los Angeles', 'San Francisco');

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3.单项选择题 The EMPLOYEES table has these columns:
LAST_NAME VARCHAR2(35)
SALARY NUMBER(8,2)
HIRE_DATE DATE
Management wants to add a default value to the SALARY column. You plan to alter the table by using this SQL statement:
ALTER TABLE EMPLOYEES
MODIFY (SALARY DEFAULT 5000);
Which is true about your ALTER statement?（）

A.Column definitions cannot be altered to add DEFAULT values.
B.A change to the DEFAULT value affects only subsequent insertions to the table.
C.Column definitions cannot be altered to add DEFAULT values for columns with a NUMBER data type.
D.All the rows that have a NULL value for the SALARY column will be updated with the value 5000.

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4.单项选择题 Click the Exhibit button to examine the data of the EMPLOYEES table.
Which statement lists the ID, name, and salary of the employee, and the ID and name of the employee's manager, for all the employees who have a manager and earn more than 4000?（）

A.SELECT employee_id "Emp_id", emp_name "Employee", salary, employee_id "Mgr_id", emp_name "Manager" FROM employees WHERE salary > 4000;
B.SELECT e.employee_id "Emp_id", e.emp_name "Employee", e.salary, m.employee_id "Mgr_id", m.emp_name "Manager" FROM employees e JOIN employees m WHERE e.mgr_id = m.mgr_id AND e.salary > 4000;
C.SELECT e.employee_id "Emp_id", e.emp_name "Employee", e.salary, m.employee_id "Mgr_id", m.emp_name "Manager" FROM employees e JOIN employees m ON (e.mgr_id = m.employee_id) AND e.salary > 4000;
D.SELECT e.employee_id "Emp_id", e.emp_name "Employee", e.salary, m.mgr_id "Mgr_id", m.emp_name "Manager" FROM employees e SELF JOIN employees m WHERE e.mgr_id = m.employee_id AND e.salary > 4000;
E.SELECT e.employee_id "Emp_id", e.emp_name "Employee", e.salary, m.mgr_id "Mgr_id" m.emp_name "Manager" FROM employees e JOIN employees m USING (e.employee_id = m.employee_id) AND e.salary > 4000;

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5.单项选择题A subquery can be used to（）.

A.create groups of data
B.sort data in a specific order
C.convert data to a different format
D.retrieve data based on an unknown condition

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6.单项选择题Mary has a view called EMP_DEPT_LOC_VU that was created based on the EMPLOYEES, DEPARTMENTS, and LOCATIONS tables. She granted SELECT privilege to Scott on this view. Which option enables Scott to eliminate the need to qualify the view with the name MARY.EMP_DEPT_LOC_VU each time the view is referenced?（）

A.Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command CREATE PRIVATE SYNONYM EDL_VU FOR mary.EMP_DEPT_LOC_VU; then he can prefix the columns with this synonym.
B.Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command CREATE SYNONYM EDL_VU FOR mary.EMP_DEPT_LOC_VU; then he can prefix the columns with this synonym.
C.Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command CREATE LOCAL SYNONYM EDL_VU FOR mary.EMP_DEPT_LOC_VU; then he can prefix the columns with this synonym.
D.Scott can create a synonym for the EMP_DEPT_LOC_VU by using the command CREATE SYNONYM EDL_VU ON mary(EMP_DEPT_LOC_VU); then he can prefix the columns with this synonym.
E.Scott cannot create a synonym because synonyms can be created only for tables.
F.Scott cannot create any synonym for Mary's view. Mary should create a private synonym for the view and grant SELECT privilege on that synonym to Scott.

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7.单项选择题 The EMP table contains these columns:
EMPLOYEE_ID NUMBER(4)
EMPNAME VARCHAR2 (25)
SALARY NUMBER(9,2)
HIRE_DATE DATE
You query the database with this SQL statement:
SELECT empname,hire_date HIREDATE, salary
FROM EMP
ORDER BY hire_date;
How will the results be sorted?（）

A.randomly
B.ascending by date
C.descending by date
D.ascending alphabetically
E.descending alphabetically

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8.多项选择题Evaluate the SQL statement: TRUNCATE TABLE DEPT;Which three are true about the SQL statement? （）

A.It releases the storage space used by the table.
B.It does not release the storage space used by the table.
C.You can roll back the deletion of rows after the statement executes.
D.You can NOT roll back the deletion of rows after the statement executes.
E.An attempt to use DESCRIBE on the DEPT table after the TRUNCATE statement executes will display an error.
F.You must be the owner of the table or have DELETE ANY TABLE system privileges to truncate the DEPT table.

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9.单项选择题 The EMPLOYEES table contains these columns: LAST_NAME VARCHAR2 (25)
SALARY NUMBER (6,2)
COMMISSION_PCT NUMBER (6)
You need to write a query that will produce these results:
1.Display the salary multiplied by the commission_pct.
2.Exclude employees with a zero commission_pct.
3.Display a zero for employees with a null commission value.
Evaluate the SQL statement:
SELECT LAST_NAME, SALARY*COMMISSION_PCT
FROM EMPLOYEES
WHERE COMMISSION_PCT IS NOT NULL;
What does the statement provide?（）

A.all of the desired results
B.two of the desired results
C.one of the desired results
D.an error statement

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10.多项选择题Which three are DATETIME data types that can be used when specifying column definitions? （）

A.TIMESTAMP
B.INTERVAL MONTH TO DAY
C.INTERVAL DAY TO SECOND
D.INTERVAL YEAR TO MONTH
E.TIMESTAMP WITH DATABASE TIMEZONE

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