You need to modify the STUDENTS table ...

单项选择题You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty. Which statement accomplishes this task?（）

A.ALTER TABLE students ADD PRIMARY KEY student_id;
B.ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);
C.ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;
D.ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
E.ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);

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1.多项选择题 Click the Exhibit button and 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 be performed 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 COMMISSION 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 than 800

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2.单项选择题 Evaluate this SQL statement:
SELECT e.EMPLOYEE_ID,e.LAST_NAME,e.DEPARTMENT_ID, d.DEPARTMENT_NAME
FROM EMPLOYEES e, DEPARTMENTS d
WHERE e.DEPARTMENT_ID = d.DEPARTMENT_ID;
In the statement, which capabilities of a SELECT statement are performed?（）

A.selection, projection, join
B.difference, projection, join
C.selection, intersection, join
D.intersection, projection, join
E.difference, projection, product

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3.单项选择题 Click the Exhibit button and examine the data from the ORDERS and CUSTOMERS tables.
Evaluate this SQL statement:
SELECT cust_id, ord_total
FROM orders
WHERE ord_total > ANY(SELECT ord_total
FROM orders
WHERE cust_id IN (SELECT cust_id
FROM customers WHERE city LIKE'New York'));
What is the result when the above query is executed?（）

A.A
B.B
C.C
D.D
E.E

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4.单项选择题 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*FROMemp_dept_vu；
B.SELECTdepartment_id，SUM（salary）FROMemp_dept_vuGROUPBYdepartment_id；
C.SELECTdepartment_id，job_id，AVG（salary）FROMemp_dept_vuGROUPBYdepartment_id，job_id；
D.SELECTjob_id，SUM（salary）FROMemp_dept_vuWHEREdepartment_idIN（10，20）GROUPBYjob_idHAVINGSUM（salary）>；20000；
E.Noneofthestatementsproduceanerror；allarevalid

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5.多项选择题 Examine the SQL statement that creates ORDERS table:
CREATE TABLE orders
(SER_NO NUMBER UNIQUE,
ORDER_ID NUMBER,
ORDER_DATE DATE NOT NULL,
STATUS VARCHAR2(10)
CHECK (status IN ('CREDIT', 'CASH')),
PROD_ID NUMBER
REFERENCES PRODUCTS(PRODUCT_ID),
ORD_TOTAL NUMBER,
PRIMARY KEY (order_id, order_date));
For which columns would an index be automatically created when you execute the above SQL statement? （）

A.SER_NO
B.ORDER_ID
C.STATUS
D.PROD_ID
E.ORD_TOTAL
F.composite index on ORDER_ID and ORDER_DATE

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6.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;

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7.单项选择题 Evaluate the set of SQL statements:
CREATE TABLE dept
(deptno NUMBER(2),
dname VARCHAR2(14),
loc VARCHAR2(13));
ROLLBACK;
DESCRIBE DEPT
What is true about the set?（）

A.The DESCRIBE DEPT statement displays the structure of the DEPT table.
B.The ROLLBACK statement frees the storage space occupied by the DEPT table.
C.The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.
D.The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.

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8.多项选择题Which are DML statements?（）

A.COMMIT
B.MERGE
C.UPDATE
D.DELETE
E.CREATE
F.DROP...

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9.单项选择题Evaluate the SQL statement:SELECT ROUND(45.953, -1), TRUNC(45.936, 2)FROM dual;Which values are displayed?（）

A. 46 and 45
B. 46 and 45.93
C. 50 and 45.93
D. 50 and 45.9
E. 45 and 45.93
F. 45.95 and 45.93

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10.多项选择题 Examine the structure of the EMPLOYEES table:
EMPLOYEE_ID NUMBER Primary Key
FIRST_NAME VARCHAR2(25)
LAST_NAME VARCHAR2(25)
Which three statements insert a row into the table? （）

A.INSERT INTO employees VALUES ( NULL, 'John', 'Smith');
B.INSERT INTO employees( first_name, last_name) VALUES( 'John', 'Smith');
C.INSERT INTO employees VALUES ( '1000', 'John', NULL);
D.INSERT INTO employees (first_name, last_name, employee_id) VALUES ( 1000, 'John', 'Smith');
E.INSERT INTO employees (employee_id) VALUES (1000);
F.INSERT INTO employees (employee_id, first_name, last_name) VALUES ( 1000, 'John', ' ');

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