多选题以下是客户(CUSTOMER)表和客户_订单(CURR_ORDER)表的结构：
CUSTOMER
------------------------------------
CUSTOMER_ID NUMBER(5)
NAME VARCHAR2(25)
CREDIT_LIMIT NUMBER(8, 2)
ACCT_OPEN_DATE DATE
CURR_ORDER
------------------------------------
ORDER_ID NUMBER(5)
CUSTOMER_ID NUMBER(5)
ORDER_DATE DATE
TOTAL NUMBER(8, 2)
以下哪种情况下应该使用子查询来返回所需的结果?
多选题下面哪条语句正确描述了与多段备份相关的动态性能视图和数据字典视图?
多选题Given:
2. public class Later {
3. public static void main(String[] args) {
4. boolean earlyExit = new Later().testl(args);
5. if(earlyExit) assert false;
6. new Later() .test2(args);
7. }
8. boolean test1 (String[] a) {
9. if (a.length == 0) return false;
10. return true;
11. }
12. private void test2(String[] a) {
13. if (a.length == 2) assert false;
14. } }
Which are true? (Choose all that apply.)
多选题以下是INVENTORY(库存)表中每一列的详细定义： Column Name ID_HUMBER DESCRIPTION MANUFACTURER_ID QUANTITY PRICE ORDER_DATE Key Type PK FK Nulls/Unique HN, U NN NN FK Table MANUFACTURER FK Column ID_NUMBER Datatype NUM VARCHAR2 VARCHAR2 NUM HUM DATE Length 9 25 26 9 8, 2 要删除1997年7月25目之后的任何一个指定的库存记录(即具有一个特定标识号码的库存记录)，请问在如下的语句中使用哪个来完成此项操作? A．DELETE FROM inventory WHERE order_date＞'25-JUL-1997' AND id_number= B．DROP FROM inventory WHERE order_date＞TO_DATE('25-JUL-97') AND id_number= C．DELETE FROM inventory WHERE order_date=＞'25-JUL-97' AND id_number=' D．DELETE FROM inventory WHERE order_date＞('25-JUL-1997') OR id_number= E．DELETE FROM inventory WHERE order_date＞TO_DATE('July 25, 1997', 'DD.MM.YYYY') AND id_number=
多选题Given:
2. class SafeDeposit {
3. private static SafeDeposit singleton;
4. public static SafeDeposit getInstance(int code) {
5. if(singleton == null)
6. singleton = new SafeDeposit(code);
7. return singleton;
8. }
9. private int code;
10. private SafeDeposit(int c) { code = c; }
11. int getCode() {return code; }
12. }
13. public class BeSafe {
14. // insert lots of code here
25. }
Which are true? (Choose all that apply.)
多选题在一个查询语句的哪些子句中可以使用替代变量?
多选题Given:
3. public class RediMix extends Concrete {
4. RediMix() {System.out.println("r "); }
5. public static void main(String[] args) {
6. new RediMix();
7. }
8. }
9. class Concrete extends Sand {
10. Concrete() {System.out.print("c ");
11. private Concrete(String s) { }
12. }
13. abstract class Sand {
14. Sand() {System.out.print("s "); }
15. }
What is the result?
多选题要修改PRODUCT(产品)表中的PRODUCT_NAME(产品名)这一列的内容，请问可以使用以下DML语句的哪两个? A．ALTER B．MERGE C．UPDATE D．COMMIT E．INSERT F．MODIFY
多选题Given that FileNotFoundException extends IOException and given:
2. import java.io.*;
3. public class Changeup {
4. public static void main(String[] args) throws IOException {
5. new Changeup() .go();
6. new Changeup() .go2();
7. new Changeup() .go3();
8. }
9. void go() {throw new IllegalArgumentException(); }
10.
11. void go2() throws FileNotFoundException { }
12.
13. void go3() {
14. try {throw new Exception(); }
15. catch (Throwable th) {throw new NullPointerException(); }
16. } }
What is the result? (Choose all that apply.)
多选题下面哪些RMAN命令不能正确配置保留策略?
多选题Given:
5. class OOthing {void doStuff() {System.out.print("oo "); } }
6. class GuiThing extends OOthing {
7. void doStuff() {System.out.print("gui "); }
8. }
9. public class Button extends GuiThing {
10. void doStuff() {System.out.print("button "); }
11. public static void main(String[] args) {new Button().go();}
12. void go() {
13. GuiThing g = new GuiThing();
14. // this.doStuff();
15. // super.doStuff();
16. // g.super.doStuff();
17. // super.g.doStuff();
18. // super.super.doStuff();
19. } }
If the commented lines are uncommented independently, which are true? (Choose all that apply.)
多选题用户wuda基于jinlian模式(用户)中已经存在的EMPLOYEE表创建了一个私有同义词。请问，在如下的语句中，他将使用哪一个语句?
多选题When using the java.io.Console class, which are tree? (Choose all that apply.)
多选题Given:
2. import java.util.*;
3. public class Foggy extends Murky {
4. public static void main(String[] args) {
5. final List＜String＞ s = new ArrayList＜String＞();
6. s.add("a"); s.add("f"); s.add("a");
7. new Foggy() .mutate(s);
8. System.out.println(s);
9. }
10. List＜String＞ mutate (List＜String＞ s) {
11. List＜String＞ ms = s;
12. ms.add ("c");
13. return s;
14. }
15. }
16. class Murky {
17. final void mutate(Set s) { }
18. }
What is the most likely result?
多选题一个扩展ROWID与一个限制性ROWID之间有哪些不同? A．一个扩展ROWID需要10字节的磁盘存储空间 B．一个扩展ROWID限制数据库最多可以有1022个数据文件 C．扩展ROWID目前已经不再使用了 D．扩展ROWID并不是使用一种基于64位的编码方案显示的
多选题Given:
1. class c1 { }
2. class c2 { }
3. interface i1 { }
4. interface i2 { }
5. class A extends c2 implements i1 { }
6. class B implements i1 implements i2 { }
7. class C implements c1 { }
8. class D extends cl, implements i2 { }
9. class E extends i1, i2 { }
10. class F implements i1, i2 { }
What is the result? (Choose all that apply.)
A. Class A does not compile.
B. Class B does not compile.
C. Class C does not compile.
D. Class D does not compile.
E. Class E does not compile.
E. Class F does not compile.
G. Compilation succeeds for all of the classes.
多选题哪个RMAN参数控制多路复用到磁盘和磁带?
多选题Given:
2. class Chilis {
3. Chilis (String c, int h) {color = c; hotness = h; }
4. String color;
5. int hotness;
6. public boolean equals(Object o) {
7. if(this == (Chilis)o) return true;
8. return false;
9. }
10. public String toString() {return color + " " + hotness; }
11. }
If instances of class Chilis are to be used as keys in a Map, which are true? (Choose all that apply.)
多选题在如下的操作中，哪一个将造成一个用户进程与Oracle服务器建立起连接? A．退出SQL*Plus B．在SQL*Plus中执行一个SQL脚本 C．在SQL*Plus中发出一个SELECT语句 D．在SQL*Plus中发出"connect cat/miao"命令
多选题你已经在恢复目录数据库以及包含RMAN目录的表空间中丢失了最近归档的重做日志文件。此时，可以对恢复目录数据库进行不完整还原，以便还原到在恢复目录中注册目标数据库后的一个时间点。可以使用什么命令来重新同步目标数据库的元数据(及备份信息)和恢复目录数据库?