The EMPLOYEES table has these columns:LAST_NAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATEManagement 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 DEFAUL

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The EMPLOYEES table has these columns:LAST_NAME VARCHAR2(35) SALARY NUMBER(8,2) HIRE_DATE DATEManagement 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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第1题：

Examine the data in the EMPLOYEES and DEPARTMENTS tables:Also examine the SQL statements that create the EMPLOYEES and DEPARTMENTS tables:On the EMPLOYEES table, EMPLOYEE_ID is the primary key.MGR_ID is the ID of managers and refers to the EMPLOYEE_ID.DEPT_ID is foreign key to DEPARTMENT_ID column of the DEPARTMENTS table.On the DEPARTMENTS table, DEPARTMENT_ID is the primary key.Examine this DELETE statement:What happens when you execute the DELETE statement?（）

A. Only the row with department ID 40 is deleted in the DEPARTMENTS table.

B. The statement fails because there are child records in the EMPLOYEES table with department ID 40.

C. The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 110 and 106 are deleted from the EMPLOYEES table.

D. The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 106 and 110 and the employees working under employee 110 are deleted from the EMPLOYEES table.

E. The row with department ID 40 is deleted in the DEPARTMENTS table. Also all the rows in the EMPLOYEES table are deleted.

F. The statement fails because there are no columns specifies in the DELETE clause of the DELETE statement.

参考答案：B

第2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;

正确答案:D,E

第3题：

You added a PHONE_NUMBER column of NUMBER data type to an existing EMPLOYEES table. The EMPLOYEES table already contains records of 100 employees. Now, you want to enter the phone numbers of each of the 100 employees into the table. Some of the employees may not have a phone number available. Which data manipulation operation do you perform? （）

A. MERGE

B. INSERT

C. UPDATE

D. ADD

E. ENTER

F. You cannot enter the phone numbers for the existing employee records.

参考答案：C

第4题：

User Scott has updated the salary of one of the employees in the EMPLOYEES table and has not committed the transaction. What are the two types of locks that this scenario would lead to？（）

A、null lock on the row being updated
B、null lock on the table containing the row
C、ROW SHARE lock for the row being updated
D、ROW EXCLUSIVE lock for the row being updated
E、shared row-exclusive lock for the row being updated
F、a shareable table lock for the table containing the row
G、exclusive table-level lock for the table containing the row

正确答案:D,F

第5题：

A、MERGE
B、INSERT
C、UPDATE
D、ADD
E、ENTER
F、You cannot enter the phone numbers for the existing employee records.

正确答案:C

第6题：

Which two statements complete a transaction?（）

A、DELETE employees;
B、DESCRIBE employees;
C、ROLLBACK TO SAVE POINT C;
D、GRANT SELECT ON employees TO SCOTH
E、ALTER TABLE employees SET UNUSED COLUMN sal;
F、Select MAX(sal) FROM employees WHERE department _ id 20;

正确答案:D,E

第7题：

In which situations does the Oracle Data Pump use external tables and not the direct path load whileexporting a table（）

A、if a table is not in a cluster
B、if a table has an active trigger
C、if a table has an encrypted
D、if a table has a column of data type LONG defined on it
E、if a table has a referential integrity constraint defined on it

正确答案:B,C,E

第8题：

Examine the data from the EMP table:The COMMISSION column shows the monthly commission earned by the employee.Which three tasks would require subqueries or joins in order to perform in a single step?（）

A. Deleting the records of employees who do not earn commission.

B. Increasing the commission of employee 3 by the average commission earned in department 20.

C. Finding the number of employees who do NOT earn commission and are working for department 20.

D. Inserting into the table a new employee 10 who works for department 20 and earns a commission that is equal to the commission earned by employee 3.

E. Creating a table called COMMISSION that has the same structure and data as the columns EMP_ID and COMMISSIONS of the EMP table.

F. Decreasing the commission by 150 for the employees who are working in department 30 and earning a commission of more then 800.

参考答案：B, D, F

第9题：

Which two operations can be flashed back using the Flashback technology？（）

A、DROP USER SMITH；
B、DROP TABLE EMPLOYEES；
C、DROP TABLESPACE USERS；
D、ALTER TABLE SALES_REP DROP PARTITION P1；
E、ALTER TABLE EMPLOYEES DROP COLUMN DESIG_ID；

正确答案:A,B

第10题：

You have just performed a FLASHBACK TABLE operation using the following command： flashback table employees to scn 123456； The employees table has triggers associated with it. Which of the following statements is true regarding the state of the triggers during the Flashback Table operation？（）

A、 All the triggers are disabled.
B、 All the triggers are enabled by default.
C、 Enabled triggers remain enabled and disabled triggers remain disabled.
D、 Triggers are deleted when a Flashback Table operation is performed.

正确答案:A

The EMPLOYEES table has these co

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