多选题如果要将INVENTORY表的表名更改为PARTS，应使用以下哪个语句?
多选题在以下有关序列(sequence)的语句中，哪个是正确的? A．一个序列(sequence)只能用于创建主键的值 B．一个序列(sequence)可以用于相同模式(用户)中的多个表 C．创建一个序列会使表中的序列号缩短 D．在内存中缓存(存储)序列值会降低序列访问序列值的效率
多选题应该使用如下哪个命令显示视图PARTS_VU的结构?
多选题Given:
4. public class Hemlock {
5. static StringBuffer sb;
6. StringBuffer sb2;
7. public static void main(String[] args) {
8. sb = sb.append(new Hemlock().go(new StringBuffer("hey")));
9. System.out.println(sb);
10. }
11. {sb2 = new StringBuffer("hi "); }
12. StringBuffer go(StringBuffer s) {
13. System.out.print(s + " oh " + sb2);
14. return new StringBuffer("ey");
15. }
16. static {sb = new StringBuffer("yo "); }
17. }
What is the result?
多选题请看如下的SQL语句，执行这个语句时将失败，请问怎样修改可以解决这一问题? SELECT c.customer_id, o.order_id, o.order_date, p.product_name FROM customer c, curr_order o, product p WHERE customer.customer_id=curr_order.customer_id AND oproduct_id=p.product_id ORDER BY o.ordei_amount; A．在ORDER BY子句中使用表名 B．将表的别名从WHERE子句中去掉 C．在SELECT列表中包括order_amount列 D．在WHERE子句中使用表的别名以替代表名 E．从ORDER BY子句中去掉表的别名并且只使用列名
多选题如果QUANTITY的值为空值(null)，在执行以下哪个语句时会显示一个0?
多选题以下哪个操作符最适用于单行子查询?
多选题使用如下的SQL语句查询数据库：
SELECT id_number, 100/quantity
FROM inventory;
如果QUANTITY的值为空值(NULL)，Oracle将显示哪个值?
多选题Given:
1. public class Hose ＜E extends Hose＞ {
2. E innerE;
3. public static E doStuff(E e, Hose＜E＞ e2) {
4. // insert code here
5. }
6. public E getE() {
7. return innerE;
8. } }
Which can be inserted, independently at line 4, for the code to compile? (Choose all that apply.)
多选题Given:
2. public class Alamo {
3. public static void main(String[] args) {
4. try {
5. assert(!args[0] .equals("x")) : "kate";
6. } catch(Error e) {System.out.print("ae "); }
7. finally {
8. try {
9. assert(!args[0] .equals("y")) : "jane";
10. } catch(Exception e2) {System.out.print("ae2 ");
11. finally {
12. throw new IllegalArgumentException();
13. } } } }
And, if the code compiles, the invocation:
java -ea Alamo y
Which will be included in the output? (Choose all that apply.)
多选题以下单行函数中的哪一个可以用于VARCHAR2列? A．NVL B．ROUND C．TRUNC D．SYSDATE
多选题Given that "it, IT" is the locale code for Italy and that "pt, BR" is the locale code for Brazil, and given:
51. Date d = new Date();
52. DateFormat df = DateFormat.getDateInstance(DateFormat. FULL);
53. Locale[] la = {new Locale("it", "IT"), new Locale("pt", "BR")};
54. for(Locale l: la) {
55. df.setLocale(1);
56. System.out.println(df.format(d));
57. }
Which are true? (Choose all that apply.)
多选题以下是表SERVICE中的内容，如果使用如下的查询语句，哪个MACHINE_ID将最后一个显示?SELECTmachine_id,service_dateFROMserviceORDERBYtechnician_id,service_date;A．458745B．687523C．785214D．789874E．980076
多选题请看如下的DDL语句： CREATE TABLESPACE wuda_data DATAFILE '/disk12/wuda_data.dbf' SIZE 100M MINIMUM EXTENT 500K DEFAULT STORAGE (INITIAL 100K NEXT 100K MAXEXTENTS 500 PCTINCREASE 0); 为什么以上这一创建表空间的DDL语句会失败? A．MAXEXTENTS设置的值太高 B．INITIAL和NEXT应该设置成MINIMUM EXTENT的整数倍 C．对于这个默认的存储参数来说该数据文件太大了 D．MINIMUM EXTENT不能够在表空间以一级设置
多选题使用如下的DDL语句创建一个名为PARTS_VU的视图，请问基于这个视图，可以使用哪个命令? CREATE FORCE VIEW parts_vu (company, contact) AS SELECT manufacturername, contact_name FROM inventory WITH READ ONLY; A．UPDATE B．DELETE C．SELECT D．INSERT
多选题Given a directory structure:
- baseDir
- testDir
- subDir2
- Shackelton.txt
and given the following code:
12. String name = "testDir" + File.pathSeparator + "subDir2" + File.pathSeparator + "Shackelton.txt";
13. File f = new File (name);
14. System.out.println("exists " + f.exists());
Assuming the proper import statements and exception handling, which statements must be true in order for the output to be "exists true"? (Choose three.)
多选题Given:
3. class Stereo {void makeNoise() {assert false; } }
4. public class BoomBox extends Stereo {
5. public static void main(String[] args) {
6. new BoomBex() .go(args);
7. }
8. void go(String[] args) {
9. if(args.length ＞ 0) makeNoise();
10. if(!args[0] .equals ("x")) System.out.println("!x");
11. } }
And, if the code compiles, the invocation:
java -ea BoomBox
What is the result?
多选题Given:
2. abstract interface Pixie {
3. abstract void sprinkle();
4. static int dust = 3;
5. }
6. abstract class TinkerBell implements Pixie {
7. String fly() {return "flying "; }
8. }
9. public class ForReal extends TinkerBell {
10. public static void main(String[] args) {
11. new ForReal() .sprinkle();
12. }
13. public void sprinkle() {System.out.println(fly() + " " + dust);}
14. }
What is the result? (Choose all that apply.)
多选题ACCOUNT表包括了如下的列： ACCOUNT_ID NUMBER(12) NEW_BALANCE NUMBER(7, 2) PREV_BALANCE NUMBER(7, 2) FINANCE_CHARGE NUMBER(7, 2) 如果要用最简单的方法显示ACCOUNT表中所有的记录，则应该使用以下哪个查询语句? A．SELECT*FROM account; B．SELECT any FROM account; C．SELECT all FROM account; D．SELECT account_id, new_balance, prev_balance, finance_charge FROM account;
多选题在将投影(projection)操作与选择(selection)操作进行比较时，以下的陈述哪个是正确的?