多选题为了恢复操作,Oracle服务器会将变化的数据记录到以下什么地方? A.数据文件 B.追踪文件 C.控制文件 D.重做日志文件 E.参数文件
多选题Given:
2. class Dog {
3. void makeNoise() { System.out.print,("bark ") ; }
4. static void play() { System.out.print("catching ");
5. }
6. class Bloodhound extends Dog {
7. void makeNoise() {System.out.print("howl "); }
8. public static void main(String[] args) {
9. new Bloodhound() .go();
10. super.play();
11. super.makeNoise();
12. }
13. void go() {
14. super.play();
15. makeNoise();
16. super.makeNoise();
17. } }
What is the result? (Choose all that apply.)
多选题有关控制文件的配置,Oracle所推荐的最低要求是什么? A.一个控制文件 B.两个控制文件放在同一个硬盘上 C.两个控制文件放在不同的硬盘上 D.3个控制文件放在同一个硬盘上 E.3个控制文件分别放在不同的硬盘上
多选题Given:
2. public class Errrrr {
3. static String a = null;
4. static String s = "";
5. public static void main(String[] args) {
6. try {
7. a = args[0];
8. System.out.print(a);
9. s += "t1 ";
10. }
11. catch (RuntimeException re) {s += "c1 "; }
12. finally {s += "f1 "; }
13. System.out.println(" " + s);
14. } }
And two command-line invocations:
java Errrrr
java Errrrr x
What is the result?
多选题如果查询数据字典V$LOGFILE并发现GROUP 3中的log3a.log成员的STATUS(列的)是空白的,请问在以下有关这一文件(成员)的陈述中,哪一个是正确的? A.它正在使用 B.它是不完整的 C.它是不可访问的 D.对于恢复来说,它已经不再需要了
多选题Given:
2. public class Incomplete {
3. public static void main(String[] args) { // change code here?
4. // insert code here?
5. new Incomplete() .doStuff();
6. // insert code here?
…
10. }
11. static void doStuff() throws Exception
12. throw new Exception();
13. }
Which are true? (Choose all that apply.)
多选题以下是CLASS(课程)表和INSTRUCTOR(教师)表中所存储的数据: CLASS CLASS_ID CLASS_NAME HOURS_CREDIT INSTRUCTOR_ID 1 Introduction to Accounting 3 4 2 Computer Basics 3 1 3 Tax Accounting Principles 3 4 4 American History 3 2 5 Basic Engineering 3 INSTRUCTOR INSTRUCTOR_ID LAST_NAME FIRST_NAME 1 Chao Ling 2 Vanderbilt Herbert 3 Wigley Martha 4 Page Albert 要删除没有指派教师(INSTRUCTOR)的课程(CLASS),在如下的DELETE语句中,哪一个将获取所希望的结果? A.DELETE class_id, class_name, hours_credit, instructor_id FROM class WHERE instructor_id IS NULL; B.DELETE FROM class WHERE instructor_id NOT IN (SELECT instructor_id FROM class); C.DELETE FROM instructor NATURAL JOIN class WHERE instructor_id IS NOT NULL; D.DELETE FROM class WHERE instructor_id IS NULL;
多选题Given:
2. class RainCatcher {
3. static StringBuffer s;
4. public static void main(String[] args)
5. Integer i = new Integer(42);
6. for(int j = 40; j < i; i--)
7. switch(i) {
8. case 41: s.append("41 ");
9. default: s.append("def ");
10. case 42: s.append("42 ");
11. }
12. System.out.println(s);
13. } }
What is the result?
多选题以下是学生(STUDENT)表所包含的全部列的定义:
ID NUMBER(9) PK
LAST_NAME VARCHAR2(25)
FIRST_NAME VARCHAR2(25)
ENROLL_DATE DATE
请看如下的SQL脚本(语句),应该怎样修改才可以使它运行?
ACCEPT id "Please enter the student id: "
SELECT id, last_name, first_name, enroll_date
FROM student
WHERE id=&id
/
多选题Given:
1. import java.util.*;
2. public class Analyzer {
3. static List<Exception> me;
4. Exception myEx;
5. public static void main(String[] args) {
6. Analyzer[] aa = {new Analyzer(), new Analyzer()};
7. me = new ArrayList<Exception>();
8. for(int i = 0; i < 2; i++) {
9. try {
10. if(i == 0) throw new Exception();
11. if(i == i) throw new MyException();
12. }
13. catch (Exception e) {
14. me.add(e);
15. aa[i] .myEx = e;
16. }
17. }
18. System.out.println(aa.length + " " + me.size());
19. aa = null; me = null;
20. // do more stuff
21. } }
22. class MyException extends Exception { }
When line 20 is reached, how many objects are eligible for garbage collection?
多选题在以下有关更改一个视图结构的语句中,哪一个是正确的?
多选题在以下有关数据库写进程(DBWn)的陈述中,哪4个是正确的? A.DBWn每三秒写一次磁盘 B.每当时间间隔到时DBWn写盘 C.每当校验点发生时DBWn写盘 D.每当事务提交时DBWn写盘 E.每当一个表空间被设置为只读模式时DBWn写盘 F.每当脏数据缓冲区达到限定的阈值时DBWn写盘
多选题Given:
3. class IcelandicHorse {
4. void tolt() {System.out.print("4-beat "); }
5. }
6. public class Vafi extends IcelandicHorse {
7. public static void main(String[] args) {
8. new Vafi() .go();
9. new IcelandicHorse() .tolt();
10. }
11. void go() {
12. IcelandicHorse h1 = new Vafi();
13. hl.tolt()
14. Vafi v = (Vafi) h1;
15. v.tolt();
16. }
17. void tolt() {System.out.print("pacey "); }
18. }
What is the result? (Choose all that apply.)
多选题假设要为PROGRAM_HIST表创建一个索引,这个表有数千万行数据。在每一个季度结束时,有100多万行新数据插入到该表中。在这个表上的查询多数是基于SHOW_ID列,而该列总共有不到100个不同的值。请问,应该为PROGRAM_HIST表创建一个什么类型的索引? A.位图索引 B.B-树索引 C.反转关键字索引 D.基于函数的索引
多选题以下哪个后台进程将数据库中的脏缓冲区中的数据写到数据文件中? A.日志写进程(LGWR) B.系统监督进程(SMON) C.进程监督进程(PMON) D.数据库写进程(DBWn)
多选题下面的哪些列未显示在数据字典视图FLASHBACK_TRANSACTION_QUERY中?
多选题以下是EMPLOYEE表的详细定义,其中也包括了约束的描述。 EMPLOYEE Column Name EMPLOYEE_ID NAME JOB MANAGER DATE_HIRED SALARY BONUS DEPIARTMENT_ID Key-Type PK Nulls/Unique NN,U NN NN FK Table FK Column Datatype HUM VARCHAR2 VARCHAR2 NUM DATE NUM HUM NUM Length 6 20 9 6 7, 2 7, 2 2 基于这个EMPLOYEE表创建了一个视图,并允许用户通过这个视图向EMPLOYEE表中插入数据。请问,在如下的语句中,应该使用哪个语句创建这个视图? A.CREATE VIEW department_v AS SELECT DISTINCT department FROM employee; B.CREATE VIEW emp_info_v AS SELECT employee_id, name, job, manager FROM employee; C.CREATE VIEW emp_info_v AS SELECT employee_id, name, job, manager, department_id, date_hired FROM employee; D.CREATE VIEW dept_salary_v AS SELECT department_id,AVG (salary) "average salary" FROM employee GROUP BY department_id;
多选题Given:
1. import java.util.*;
2. public class Elway {
3. public static void main(String[] args) {
4. ArrayList[] ls = new ArrayList[3];
5. for(int i = 0; i < 3; i++) {
6. ls[i] = new ArrayList();
7. ls[i].add("a" + i);
8. }
9. Object o = ls;
10. do3(ls) ;
11. for(int i = 0; i < 3; i++) {
12. // insert code here
13. }
14. }
15. static Object do3(ArrayList[] a) {
16. for(int i = 0; i < 3; i++) a[i] .add("e");
17. return a;
18. } }
And the following fragments:
Ⅰ. System.out.print (o [i ] + " ");
Ⅱ. System.out.print((ArrayList[]) [i] + " ");
Ⅲ. System.out.print( ((Object[])o) [i] + " ");
Ⅳ. System.out.print(((ArrayList[])o) [i] + " ");
If the fragments are added to line 12, independently, which are true? (Choose all that apply.)
多选题要显示赋予概要文件DOG_PROJECT的资源限制信息,请问应该查询如下哪一个数据字典? A.DBA_USERS B.DBA_TABLES C.DBA_OBJECTS D.DBA_PROFILES E.DBA_TABLESPACE
多选题哪一个Oracle服务器的组件是由后台进程和内存结构所组成的? A.SGA B.一个实例(instance) C.一个重做日志文件 D.一个数据库文件