Management has asked you to calculate the value 12*salary* commission_pct for all the employees in the EMP table. The EMP table contains these columns: LAST NAME VARCNAR2(35) NOT NULL SALARY NUMBER(9,2) NOT NULL COMMISION_PCT NUMBER(4,2) Which statement

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第2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); What 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 at 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.

第3题：

Management has asked you to calculate the value 12*salary* commission_pct for all the employees in the EMP table. The EMP table contains these columns: LAST NAME VARCNAR2(35) NOT NULL SALARY NUMBER(9,2) NOT NULL COMMISION_PCT NUMBER(4,2) Which statement ensures that a value is displayed in the calculated columns for all employees?（）

• A、SELECT last_name, 12*salary* commission_pct FROM emp;
• B、SELECT last_name, 12*salary* (commission_pct,0) FROM emp;
• C、SELECT last_name, 12*salary*(nvl(commission_pct,0)) FROM emp;
• D、SELECT last_name, 12*salary*(decode(commission_pct,0)) FROM emp;

第4题：

Which SQL statement defines the FOREIGN KEY constraint on the DEPTNO column of the EMP table?（）

• A、CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) NOT NULL CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);
• B、CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));
• C、CREATE TABLE EMP (empno NUMBER(4) ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));
• D、CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp deptno fk REFERENCES dept (deptno));

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Examine the structure of the EMP_DEPT_VU view: Column Name Type Remarks EMPLOYEE_ID NUMBER From the EMPLOYEES table EMP_NAME VARCHAR2(30) From the EMPLOYEES table JOB_ID VARCHAR2(20) From the EMPLOYEES table SALARY NUMBER From the EMPLOYEES table DEPARTMENT_ID NUMBER From the DEPARTMENTS table DEPT_NAME VARCHAR2(30) From the DEPARTMENTS table Which SQL statement produces an error?（）

• A、SELECT * FROM emp_dept_vu;
• B、SELECT department_id, SUM(salary) FROM emp_dept_vu GROUP BY department _ id;
• C、SELECT department_id, job_id, AVG(salary) FROM emp_dept_vu GROUP BY department _ id, job_id;
• D、SELECT job_id, SUM(salary) FROM emp_dept_vu WHERE department_id IN (10,20) GROUP BY job_id HAVING SUM (salary) > 20000
• E、None of the statements produce an error; all are valid.

第6题：

Examine the structure of the EMPLOYEES, DEPARTMENTS, and TAX tables. EMPLOYEES NOT NULL, Primary EMPLOYEE_ID NUMBER Key VARCHAR2 EMP_NAME (30) VARCHAR2 JOB_ID (20) SALARY NUMBER References MGR_ID NUMBER EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table DEPARTMENTS NOT NULL, DEPARTMENT_ID NUMBER Primary Key VARCHAR2 DEPARTMENT_NAME |30| References MGR_ID column MGR_ID NUMBER of the EMPLOYEES table TAX MIN_SALARY NUMBER MAX_SALARY NUMBER TAX_PERCENT NUMBER 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 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 then 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.

第7题：

客户需要计算EMP表中所有职工12*salary* commission_pct的值.EMP表结构如下：LAST NAME VARCNAR2（35）NOT NULL SALARY NUMBER（9，2）NOT NULL COMMISION_PCTNUMBER（4，2）哪个语句可以查询计算EMP表中所有职工行？（）

• A、SELECT last_name，12*salary* commission_pct FROM emp
• B、SELECT last_name，12*salary*（commission_pct，0）FROM emp
• C、SELECT last_name，12*salary*（nvl（commission_pct，0））FROM emp如果oracle第一个参数为空那么显示第二个参数的值，如果第一个参数的值不为空，则显示第一个参数本来的值
• D、SELECT last_name，12*salary*（decode（commission_pct，0））FROM emp

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第13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

第14题：

The EMPLOYEE tables has these columns: LAST_NAME VARCHAR2(35) SALARY NUMBER(8,2) COMMISSION_PCT NUMBER(5,2) You want to display the name and annual salary multiplied by the commission_pct for all employees. For records that have a NULL commission_pct, a zero must be displayed against the calculated column. Which SQL statement displays the desired results?（）

• A、SELECT last_name, (salary * 12) * commission_pct FROM EMPLOYEES;
• B、SELECT last_name, (salary * 12) * IFNULL(commission_pct, 0) FROM EMPLOYEES;
• C、SELECT last_name, (salary * 12) * NVL2(commission_pct, 0) FROM EMPLOYEES;
• D、SELECT last_name, (salary * 12) * NVL(commission_pct, 0) FROM EMPLOYEES;

第15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

第16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 DEPARMENT_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.

第17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.

第18题：

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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