A.Asinglerowsubquerycanretrieveonlyonecolumnandonerow.
B.Asinglerowsubquerycanretrieveonlyonerowbutmanycolumns.
C.Amultiplerowsubquerycanretrievemultiplerowsandmultiplecolumns.
D.Amultiplerowsubquerycanbecomparedusingthe"；>；"；operator.
E.AsinglerowsubquerycanusetheINoperator.
F.Amultiplerowsubquerycanusethe"；="；operator.
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A.USER_CONSTRAINTS
B.USER_OBJECTS
C.ALL_CONSTRAINTS
D.USER_CONS_COLUMNS
E.USER_COLUMNS
Evaluate the SQL statement
DROP TABLE DEPT;
Which four statements are true of the SQL statement? （）
A.You cannot roll back this statement.
B.All pending transactions are committed.
C.All views based on the DEPT table are deleted.
D.All indexes based on the DEPT table are dropped.
E.All data in the table is deleted, and the table structure is also deleted.
F.All data in the table is deleted, but the structure of the table is retained.
G.All synonyms based on the DEPT table are deleted.
A.SELECT ename, salary*12 'Annual Salary' FROM employees;
B.SELECT ename, salary*12 "Annual Salary" FROM employees;
C.SELECT ename, salary*12 AS Annual Salary FROM employees;
D.SELECT ename, salary*12 AS INITCAP("ANNUAL SALARY") FROM employees
A.WHERE
B.HAVING
C.RESTRICT
D.GROUP BY
E.ORDER BY
A.The UNIQUE constraint does not permit a null value for the column.
B.A UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.
C.The PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.
D.The NOT NULL constraint ensures that null values are not permitted for the column.
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.
Examine the structure of the EMPLOYEES table:
EMPLOYEE_ID NUMBER NOT NULL
EMP_NAME VARCHAR2(30)
JOB_ID VARCHAR2(20)
SAL NUMBER
MGR_ID NUMBER
DEPARTMENT_ID NUMBER
You want to create a SQL script file that contains an INSERT statement. When the script is run, the INSERT statement should insert a row with the specified values into the EMPLOYEES table. The INSERT statement should pass values to the table columns as specified below:
EMPLOYEE_ID: Next value from the sequence
EMP_ID_SEQ EMP_NAME and JOB_ID: As specified by the user during run time, through substitution variables
SAL: 2000
MGR_ID: No value
DEPARTMENT_ID: Supplied by the user during run time through substitution variable. The INSERT statement should fail if the user supplies a value other than 20 or 50.
Which INSERT statement meets the above requirements?（）
A.INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did);
B.INSERT INTO employees VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did IN (20,50));
C.INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50)) VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did);
D.INSERT INTO (SELECT * FROM employees WHERE department_id IN (20,50) WITH CHECK OPTION) VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did);
E.INSERT INTO (SELECT * FROM employees WHERE (department_id = 20 AND department_id = 50) WITH CHECK OPTION ) VALUES (emp_id_seq.NEXTVAL, '&ename', '&jobid', 2000, NULL, &did);
A.SELECT TO_CHAR(SYSDATE,'yyyy') FROM dual;
B.SELECT TO_DATE(SYSDATE,'yyyy') FROM dual;
C.SELECT DECODE(SUBSTR(SYSDATE, 8), 'YYYY') FROM dual;
D.SELECT DECODE(SUBSTR(SYSDATE, 8), 'year') FROM dual;
E.SELECT TO_CHAR(SUBSTR(SYSDATE, 8,2),'yyyy') FROM dual;
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_ID
9998 Engineering 123
9999 Administrative Boston
You 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;
The STUDENT_GRADES table has these columns:
STUDENT_ID NUMBER(12)
SEMESTER_END DATE
GPA NUMBER(4,3)
Which statement finds the highest grade point average (GPA) per semester?（）
A.SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL;
B.SELECT (gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;
C.SELECT MAX(gpa) FROM student_grades WHERE gpa IS NOT NULL GROUP BY semester_end;
D.SELECT MAX(gpa) GROUP BY semester_end WHERE gpa IS NOT NULL FROM student_grades;
E.SELECT MAX(gpa) FROM student_grades GROUP BY semester_end WHERE gpa IS NOT NULL;
最新试题
Which are /SQL*Plus commands? （）
Which two statements about subqueries are true? （）
Which four are types of functions available in SQL? （）
Which two statements about subqueries are true? （）
User Mary has a view called EMP_DEPT_LOC_VU that was created based on the EMPLOYEES, DEPARTMENTS, and LOCATIONS tables. She has the privilege to create a public synonym, and would like to create a synonym for this view that can be used by all users of the database. Which SQL statement can Mary use to accomplish that task?（）
Which three are true? （）
Which is a valid CREATE TABLE statement? （）
Which three statements about subqueries are true? （）
Which view should a user query to display the columns associated with the constraints on a table owned by the user? （）
Which statement accomplish this? （）