1Z0-007單項選擇題每日一練(2020.05.26)

單項選擇題
Which statement explicitly names a constraint?（）
A. ALTER TABLE student_grades   ADD   FOREIGN KEY (student_id) REFERENCES students(student_id);
B. ALTER TABLE student_grades   ADD CONSTRAINT NAME = student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);
C. ALTER TABLE student_grades   ADD CONSTRAINT student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);
D. ALTER TABLE student grades   ADD NAMED CONSTRAINT student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);
E. ALTER TABLE student grades   ADD NAME student_id_fk   FOREIGN KEY (student_id) REFERENCES students(student_id);
單項選擇題
Which statement describes the ROWID data type?（）
A. Binary data up to 4 gigabytes.
B. Character data up to 4 gigabytes.
C. Raw binary data of variable length up to 2 gigabytes.
D. Binary data stored in an external file, up to 4 gigabytes.
E. A hexadecimal string representing the unique address of a row in its table.
單項選擇題
Which SQL statement displays the date March 19, 2001 in a format that appears as "Nineteenth of March 2001 12:00:00 AM"?（）
A.SELECT TO_CHAR(TO_DATE('19-Mar-2001', 'DD-Mon-YYYY'), 'fmDdspth "of" Month YYYY fmHH:MI:SS AM') NEW_DATE FROM dual;
B.SELECT TO_CHAR(TO_DATE('19-Mar-2001', 'DD-Mon-YYYY'), 'Ddspth "of" Month YYYY fmHH:MI:SS AM') NEW_DATE FROM dual;
C.SELECT TO_CHAR(TO_DATE('19-Mar-2001', 'DD-Mon-YYYY'), 'fmDdspth "of" Month YYYY HH:MI:SS AM') NEW_DATE FROM dual;
D.SELECT TO_CHAR(TO_DATE('19-Mar-2001', 'DD-Mon-YYYY'), 'fmtDdspth "of" Month YYYY fmtHH:MI:SS AM') NEW_DATE FROM dual;
單項選擇題
Examine the description of the EMPLOYEES table:EMP_ID NUMBER(4) NOT NULLLAST_NAME VARCHAR2(30) NOT NULLFIRST_NAME VARCHAR2(30)DEPT_ID NUMBER(2)Which statement produces the number of different departments that have employees with last name Smith?（）
A.SELECT COUNT(*) FROM employees WHERE last_name='Smith';
B.SELECT COUNT(dept_id) FROM employees WHERE last_name='Smith';
C.SELECT DISTINCT(COUNT(dept_id)) FROM employees WHERE last_name='Smith';
D.SELECT COUNT(DISTINCT dept_id) FROM employees WHERE last_name='Smith';
E.SELECT UNIQUE(dept_id) FROM employees WHERE last_name='Smith';
單項選擇題
Click the Exhibit button to examine the structure of the EMPLOYEES, DEPARTMENTS, and LOCATIONS tables.Two new departments are added to your company as shown: DEPARTMENT_ID DEPARTMENT_NAME MGR_ID LOCATION_ID9998 Engineering 1239999 Administrative BostonYou need to list the names of employees, the department IDs, the department names, and the cities where the departments are, even if there are no employees in the departments and even if the departments are not yet assigned to a location. You need to join the EMPLOYEES, DEPARTMENTS, and LOCATIONS tables to retrieve this information.Which statement do you execute to retrieve this information?（）
A.SELECT e.last_name, d.department_id, d.department_name, l.city FROM departments d RIGHT OUTER JOIN employees e ON d.department_id = e.department_id RIGHT OUTER JOIN locations l ON d.location_id = l.location_id;
B.SELECT e.last_name, d.department_id, d.department_name, l.city FROM departments d FULL OUTER JOIN employees e ON d.department_id = e.department_id FULL OUTER JOIN locations l ON d.location_id = l.location_id;
C.SELECT e.last_name, d.department_id, d.department_name, l.city FROM departments d LEFT OUTER JOIN employees e ON d.department_id = e.department_id LEFT OUTER JOIN locations l ON d.location_id = l.location_id;
D.SELECT last_name, department_id, department_name, city FROM departments d NATURAL JOIN employees e NATURAL JOIN locations l;