中國信保筆試題目

填空題

1、關係代數以集合代數為基礎運算，基本操作是並、差、笛卡兒積、投影和選擇。規範化理論

中分解關係模式主要是消除多餘的資料相關性。

2、數字簽名常用公開金鑰加密方法。傳送者簽名使用的'金鑰為傳送者的公鑰，

常用的加密演算法有 Hash 簽名、DSS 簽名、RSA 簽名。

3、Internet 實現組播，傳輸層協議為組播地址解析協議(MARS：Multicast Address Resolution Server)

4、完整性約束:

單個關係上的約束

not null

unique

check

參照完整性

斷言

函式依賴

簡答題

MVC 模式及其作用，列出至少兩種目前流行的 MVC 元件。

六、資料庫設計

1、建表

create table Company(companyName varchar2(30), id number(4) primary key);

create table EmployeeHired(id number(4), numberHired number(4),

FiscalYear number(4), FiscalQuarter number(4),

foreign key(id) references Company(id),

primary key(id, FiscalYear, FiscalQuarter));

2、插入資料

insert into Company values('Microsoft', 1);

insert into Company values('IBM', 2);

insert into Company values('HP', 3);

insert into Company values('Nortel', 4);

insert into EmployeeHired values(1, 1, 2007, 1);

insert into EmployeeHired values(1, 3, 2007, 3);

insert into EmployeeHired values(1, 3, 2008, 2);

insert into EmployeeHired values(2, 2, 2007, 2);

insert into EmployeeHired values(2, 4, 2007, 4);

insert into EmployeeHired values(2, 2, 2008, 1);

insert into EmployeeHired values(3, 5, 2008, 1);

insert into EmployeeHired values(3, 10, 2008, 2);

insert into EmployeeHired values(4, 3, 2008, 3);

insert into EmployeeHired values(4, 6, 2008, 4);

3、在表 Company 中加入一列 Address varchar2(40);

alter table Company

add Address varchar2(40);

4、將2008年招員工人數超過3人的公司名稱和總人數查出，按人數降序排列;

select companyName, sum(numberHired) as sum

from Company c, EmployeeHired e

where = and FiscalYear = 2008

group by , companyName

having sum(numberHired) > 3

order by sum desc;