Examine the structure of the EMPLOYEES and DEPARTMENTS tables:
EMPLOYEESColumn name Data type Remarks
EMPLOYEE_ID NUMBER NOT NULL, Primary Key
EMP_NAME VARCHAR2 (30)
JOB_ID VARCHAR2 (20)
SALARY NUMBER
MGR_ID NUMBER References EMPLOYEE_ID COLUMN
DEPARTMENT ID NUMBER Foreign key to DEPARTMENT ID
column of the DEPARTMENTS table
DEPARTMENTSColumn name Data type Remarks
DEPARTMENT_ID NUMBER NOT NULL, Primary Key
DEPARTMENT_NAME VARCHAR2(30)
MGR_ID NUMBER References MGR_ID column of the
EMPLOYEES table
Evaluate this SQL statement:
SELECT employee_id, e.department_id, department_name,
salary
FROM employees e, departments d
WHERE e. department_id = d.department_id;
Which SQL statement is equivalent to the above SQL statement?（）
A. SELECT employee_id, department_id, department_name, salary FROM employees WHERE department_id IN (SELECT department_id FROM departments);
B. SELECT employee_id, department_id, department_name, salary FROM employees NATURAL JOIN departments;
C. SELECT employee_id, d.department_id, department_name, salary FROM employees e JOIN departments d ON e.department _ id = d. department_id;
D. SELECT employee_id, department_id, department_name, Salary FROM employees JOIN departments USING (e.department_id, d.department_id);
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A. USER_TAB_PRIVS_MADE
B. USER_TAB_PRIVS
C. USER_COL_PRIVS_MADE
D. USER_COL_PRIVS
Evaluate the SQL statement:
What is the result of the statement?（）
A. The statement produces an error at line 1.
B. The statement produces an error at line 3.
C. The statement produces an error at line 6.
D. The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all departments that pay less salary then the maximum salary paid in the company.
E. The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all employees who earn less than the maximum salary in their department.
Evaluate the set of SQL statements:
CREATE TABLE dept
(deptno NUMBER(2),
dname VARCNAR2(14),
1oc VARCNAR2 (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 occupies 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.
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));
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);
A. TIMESTAMP
B. INTERVAL MONTH TO DAY
C. INTERVAL DAY TO SECOND
D. INTERVAL YEAR TO MONTH
E. TIMESTAMP WITH DATABASE TIMEZONE
Examine the data in the EMPLOYEES and DEPARTMENTS tables:
EMPLOYEES
EMP_NAME DEPT_ID MGR_ID JOB_ID SALARY
EMPLOYEE_ID
101 Smith 20 120 SA_REP 4000
102 Martin 10 105 CLERK 2500
103 Chris 20 120 IT_ADMIN 4200
104 John 30 108 HR_CLERK 2500
105 Diana 30 108 IT_ADMIN 5000
106 Smith 40 110 AD_ASST 3000
108 Jennifer 30 110 HR_DIR 6500
110 Bob 40 EX_DIR 8000
120 Ravi 20 110 SA*DIR 6500
DEPARTMENTS
DEPARTMENT_ID DEPARTMENT_NAME
10 Admin
20 Education
30 IT
40 Human Resources
Also examine the SQL statements that create the EMPLOYEES and DEPARTMENTS tables:
CREATE TABLE departments
(department_id NUMBER PRIMARY KEY,
department _ name VARCHAR2(30));
CREATE TABLE employees
(EMPLOYEE_ID NUMBER PRIMARY KEY,
EMP_NAME VARCHAR2(20),
DEPT_ID NUMBER REFERENCES
departments(department_id),
MGR_ID NUMBER REFERENCES
employees(employee id),
MGR_ID NUMBER REFERENCES
employees(employee id),
JOB_ID VARCHAR2(15).
SALARY NUMBER);
ON the EMPLOYEES,
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:
DELETE
FROM departments
WHERE department id = 40;
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.
Evaluate the SQL statement:
1 SELECT a.emp_name, a.sal, a.dept_id, b.maxsal
2 FROM employees a,
3 (SELECT dept_id, MAX(sal) maxsal
4. FROM employees
5 GROUP BY dept_id) b
6 WHERE a.dept_id = b.dept_id
7 AND a. asl < b. maxsal;
What is the result of the statement?（）
A. The statement produces an error at line 1.
B. The statement produces an error at line 3.
C. The statement produces an error at line 6.
D. The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all departments that pay less salary then the maximum salary paid in the company.
E. The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all employees who earn less than the maximum salary in their department.
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 MODIFY CONSTRAINT stud _ id _pk PRIMARY KEY (student _ id);
最新试题
Which four are types of functions available in SQL? （）
Evaluate this SQL statement:SELECT e.emp_name, d.dept_nameFROM employees eJOIN departments dUSING (department_id)WHERE d.department_id NOT IN (10,40)ORSER BY dept_name;The statement fails when executed. Which change fixes the error? （）
Evaluate these two SQL statements: SELECT last_name, salary, hire_dateFROM EMPLOYEES ORDRE BY salary DESC; SELECT last_name, salary, hire_dateFROM EMPOLYEES ORDER BY 2 DESC; What is true about them? （）
Which is an iSQL*Plus command? （）
You need to design a student registration database that contains several tables storing academic information.The STUDENTS table stores information about a student. The STUDENT_GRADES table storesinformation about the student's grades. Both of the tables have a column named STUDENT_ID. The STUDENT_ID column in the STUDENTS table is a primary key.You need to create a foreign key on the STUDENT_ID column of the STUDENT_GRADES table thatpoints to the STUDENT_ID column of the STUDENTS table. Which statement creates the foreign key?（）
Which is a valid CREATE TABLE statement? （）
You need to perform these tasks:1. Create and assign a MANAGER role to Blake and Clark2. Grant CREATE TABLE and CREATE VIEW privileges to Blake and ClarkWhich set of SQL statements achieves the desired results? （）
Which two statements about subqueries are true? （）
Examine the structure of the EMPLOYEES table:EMPLOYEE_ID NUMBER NOT NULL, Primary KeyEMP_NAME VARCHAR2(30)JOB_ID NUMBER\SAL NUMBERMGR_ID NUMBER References EMPLOYEE_ID columnDEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You created a sequence called EMP_ID_SEQ inorderto populate sequential values for the EMPLOYEE_ID column of the EMPLOYEES table. Which two statements regarding the EMP_ID_SEQ sequence are true? （）
A SELECT statement can be used to perform these three functions:1. Choose rows from a table.2. Choose columns from a table3. Bring together data that is stored in different tables by creating a link between them. Which set of keywords describes these capabilities? （）