多选题当查询数据字典DBA_USERS时，这个数据字典将显示什么信息? A．所有用户的表空间份额(quote) B．当前用户的表空间份额 C．数据库用户被创建的日期 D．当前用户在一个表空间上是否具有无限的份额

多选题使用DELETE FROM service;语句，可完成如下哪个任务?

多选题Given: 42. String s1 = " "; 43. StringBuffer s2 = new StringBuffer(" "); 44. StringBuilder s3 = new StringBuilder(" "); 45. for(int i = 0; i ＜ 1000; i++) // Loop #1 46. s1 = s1.concat("a"); 47. for(int i = 0; i ＜ 1000; i++) // Loop #2 48. s2. append ("a"); 49. for(int i = 0; i ＜ i000; i++) // Loop #3 50. s3. append ("a"); Which statements will typically be true? (Choose all that apply.)

多选题V$LOG和V$LOGFILE视图之间有什么区别?

多选题传输表空间时，DBMS_TTS.TRANSPORT_SET_CHECK的作用是什么?

多选题Given: 5. static String s = ""; 6. public static void main(String[] args) { 7. try {doStuff(args); } 8. catch (Error e) {s += "e "; } 9. s += "x "; 10. System.out.println (s); 11. } 12. static void doStuff(String[] args) { 13. if(args.length == 0) 14. throw new IllegalArgumentException(); 15. s += "d "; 16. } And, if the code compiles, and given a java invocation with no arguments, what is the result? (Choose all that apply.)

多选题如果要进行数据库配置，应该如何组织数据存储? A．将有不同备份需求的对象组织在一起 B．将具有I/O竞争需求的对象组织在一起 C．将具有不同生命周期的对象分开存放以最小化碎片问题 D．将具有静态特性的对象彼此分开存放

多选题以下是PRODUCT表和SHIPPING COST表的结构： PRODUCT --------------------------------- PRODUCT_ID NUMBER(9) PRODUCT_NAME VARCHAR2(20) COST NUMBER(5, 2) RETAIL_PRICE NUMBER(5, 2) WEIGHT NUMBER(5, 2) SHIPPING_COST --------------------------------- ID NUMBER(9) LOWWEIGHT NUMBER(5, 2) HIGHWEIGHT NUMBER(5, 2) COST NUMBER(5, 2) 如果需要显示包括了每个产品运输价格(shipping cost)的产品名(product name)，而运输价格是通过比较SHIPPING COST表中产品重量的下限和上限来计算的。现在请问，应使用如下查询语句中的哪两个语句? A．SELECT product_name, cost FROM product NATURAL JOIN shipping_cost; B．SELECT p.product_name, s.cost FROM product p, shipping_cost s WHERE p.product_id=s.id(+); C．SELECT p.product_name, s.cost FROM product p, shipping_cost s WHERE p.weight BETWEEN s.lowweight AND s.highweight; D．SELECT p.product_name, s.cost FROM product p, shipping_cost s USING (p.weight, BETWEEN s.lowweight AND s.highweight); E．SELECT p.product name.s.cost FROM product p JOIN shipping_cost s ON (p.weight BETWEEN s.lowweight AND s.highweight);

多选题什么时候索引会降低查询的速度? A．表很小 B．索引列在WHERE子句使用了 C．索引列所包含的值的范围很广 D．索引列包含了大量的空值(NULL)

多选题下面的哪些条目会临时存储在快速恢复区中?

多选题使用如下的CREATETABLE脚本(语句)创建一个名为PO_DETAIL的表。CREATETABLEpo_detail(po_numNUMBERNOTNULL,po_line_idNUMBERNOTNULL,product_idNUMBERNOTNULL,quantityNUMBER(3)NOTNULL,unitpriceNUMBER(5,2)DEFAULT0,PRIMARYKEY(po_num,po_line_id),FOREIGNKEY(po_num)REFERENCESPO_HEADER(po_num),FOREIGNKEY(product_id)REFERENCESproduct(product_id),CHECK(unit_priceBETWEEN0and9999.99))TABLESPACEUSERS;其中，PO_HEADER和PO_DETAIL表的结构和表中的数据如下：请问，在以下的INSERT语句中，哪两个将成功地执行?A．INSERTINTOpo_detail(po_num,po_line_id,product_id,unit_price,quantity)VALUES('10056','1','3','400','1052.40');B．INSERTINTOpo_detail(po_num,po_line_id,product_id)VALUES(10055,1,2);C．INSERTINTOpo_detailVALUES(10055,1,2,30,DEFAULT);D．INSERTINTOpo_detail(po_num,po_line_id,product_id,quantity,unit_price)VALUES(10052,2,3,200,NULL);E．INSERTINTOpo_detailVALUES(10056,1,3,400,52.40);F．INSERTINTOpo_detailVALUES(10055,1,2,NULL,NULL);

多选题以下是员工(EMPLOYEE)表的结构： EMPLOYEE EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_LNAME VARCHAR2(25) EMP_FNAME VARCHAR2(25) DEPT_ID NUMBER Foreign key to DEPT ID column of the DEPARTMENT table JOB_ID NUMBER Foreign key to JOB ID column of the JOB table MGR_ID NUMBER References EMPLOYEE ID column SALARY NUMBER(9, 2) HIRE_DATE DATE DOB DATE 请问，使用如下的哪个DDL语句可为EMP_LNAME列创建一个索引?

多选题请问SQL*Plus命令“SET LINESIZE 68”将完成以下的哪项工作?

多选题Given that the root directory contains a subdirectory called "office" that contains some files for a Java application, if "X" and "Y" are unknown arguments, and the following command is invoked from the root directory in order to create a JAR file containing the office directory: jar -cf X Y Which are true? (Choose all that apply.)

多选题Given: 2. class SuperCool { 3. static String os = ""; 4. void doStuff() {os += "super "; } 5. } 6. public class Cool extends SuperCool { 7. public static void main(String[] args) { 8. new Cool() .go(); 9. } 10. void go() { 11. SuperCool s = new Cool(); 12. Cool c = (Cool)s; 13. // insert code here 14. } 15. void doStuff() { os += "cool "; } 16. } If the rest of the code compiles, which line(s) of code, inserted independently at line 13, compile? (Choose all that apply.)

多选题Given: 59. Integer i1 = 2001; // set 1 60. Integer i2 = 2001; 61. System.out.println((i1 == i2) + " " + i1.equals(i2)); // output 1 62. Integer i3 = 21; // set 2 63. Integer i4 = new Integer(21); 64. System.out.println((i3 == i4) + " " + i3.equals(i4)); // output 2 65. Integer i5 = 21; // set 3 66. Integer i6 = 21; 67. System.out.println((i5 == i6) + " " + i5.equals(i6)); // output 3 What is the result? (Choose all that apply.)

多选题Given: 2. import java.util.*; 3. public class GIS { 4. public static void main(String[] args) { 5. TreeMap＜String, String＞ m1 = new TreeMap＜String, String＞(); 6. m1.put("a", "amy"); m1.put("f", "frank"); 7. NavigableMap＜String, String＞ m2 = m1.descendingMap(); 8. try { 9. m1.put("j", "john"); 10. m2.put("m", "mary"); 11. } 12. catch (Exception e) {System.out.print("ex "); } 13. m1.pollFirstEntry(); 14. System.out.println(m1 + " " + m2); 15. } } What is the result?

多选题Given: 2. public class Fabric extends Thread { 3. public static void main (String[] args) 4. Thread t=new Thread (new Fabric()); 5. Thread t2=new Thread (new Fabric()); 6. t.start(); 7. t2.start(); 8. } 9. public static void run() { 10. for(int i=0; i＜2; i++) 11. System.out.print (Thread.currentThread() .getName() +" "); 12. } 13. } Which are true? (Choose all that apply.)

多选题Given: 2. public class Self extends Thread { 3. public static void main(String[] args) 4. try { 5. Thread t = new Thread(new Self()); 6. t.start(); 7. t.start(); 8. } catch (Exception e) { System.out.print("e "); } 9. } 10. public void run() { 11. for(int i = 0; i ＜ 2; i++) 12. System.out.print(Thread.currentThread() .getName() + " " ); 13. } } Which are true? (Choose all that apply.)

多选题如要使用一个SELECT语句来显示价格(price)小于5.0的id_number，应使用如下的哪个子句? A．WHERE price＜5.00 B．HAVING price＜5.00 C．ORDER BY price＜5.00 D．GROUP BY price＜5.00