单选题下面不属于故障恢复系统处理范围的是 ____ 。

单选题有关概念结构设计，下列说法正确的是 ________ 。

单选题假设某计算机具有1 MB的内存(目前使用的计算机往往具有128 MB以上的内存)，并按字节编址，为了能存取该内存各地址的内容，其地址寄存器至少需要二进制 23 位。为了使4字节组成的字能从存储器中一次读出，要求存放在存储器中的字边界对齐，1字节的地址码应 24 。若存储器周期为200ns，且每个周期可访问4字节，则该存储器带宽为 25 b/s。假如程序员可用的存储空间为4MB，则程序员所用的地址为 26 ，而真正访问内存的地址称为 27 。

单选题In (85) software, one question of near-universal interest is how rapidly Windows NT, which began shipping last summer, will be (86) in the marketplace and for what uses. For the most part, observers are (87) about the operating system's long term prospects, but expect it to remain on (88) rather than desktops during 1994, saying that it won't become a mainstream product until (89) PCs typically have 16 to 24 MB of RAM, which is unlikely to happen next year.

单选题在关系代数的专门关系运算中，从表中选出满足某种条件的元组的操作称为 ______。

单选题与多模光纤相比较，单模光纤具 (13) 等特点。

单选题如果两名以上的申请人分别就同样的发明创造申请专利，专利权应授予 (6) 。

单选题The purpose of the requirements definition phase is to produce a clear, complete, consistent, and testable (6) of the technical requirements for the software product. During the requirements definition phase, the requirements definition team uses an iterative process to expand a broad statement of the system requirements into a complete and detailed specification of each function that the software must perform and each (7) that it must meet. The starting point is usually a set of high-level requirements from the (8) that describe the project or problem. In either case, the requirements definition team formulates an overall concept for the system and then defines (9) showing how the system will be operated, publishes the system and operations concept document, and conducts a system concept review (SCR). Following the SCR, the team derives (10) requirements for the system from the high level requirements and the system and operations concept. Using structured or object-oriented analysis the team specifies the software functions and algorithms needed to, satisfy each detailed requirement.

单选题已知关系R、S、A、B和C如下，则RUS为____。

单选题对于第7题的两个基本表，有一个SQL语句： SELECT ENO, ENAME FROM EMP WHERE DNO NOT IN (SELECT DNO FROM DEPT WHERE DNAME='金工车间');其等价的关系代数表达式是：______。

单选题在UML提供的图中， (20) 用于描述系统与外部系统及用户之间的交互； (21) 用于按时间顺序描述对象间交互。

单选题软件系统分析的任务不应该包括 (1) 。进行软件需求分析可以使用多种工具，但 (2) 是不适用的。在软件需求分析阶段中，分析员主要从用户那里解决的重要问题是 (3) 。需求规格说明书的内容不应当包括 (4) 。该文档在软件开发中具有重要的作用，其作用不应当包括 (5) 。

单选题A typical (160) language contains an applicative sub-language which approximates the mathematical abstractions of "timeless" functions applied to "spaceless" values, where the actual operation sequences and use of storage space during expression evaluation are organized behind the (161) . In this setting, values are data structures of low volume, typically a few computer words or less, which means that an illusion of spacelessness can be realized by having (162) results during expression evaluation stored at the discretion of the language implementation, and effecting parameter (163) and (164) operations through value copying.

单选题文件系统中，设立打开文件(Open)系统功能调用的基本操作是， (12) 。

单选题在结构化分析方法中，数据字典是重要的文档。对加工的描述是数据字典的组成内容之一，常用的加工描述方法 ________ 。

单选题对emp表增加雇员被雇佣时间come列，其数据类型为日期型，正确的语句是( )。 A) ALTER TABLE emp ADD come Date B) ADD TABLE emp come Date C) ALTER TABLE emp come Date D) ADD come Date TABLE emp

单选题ERP设计的总体思路中，三条干线不包含______。

单选题若有关系模式R(A,B,C)和S(C,D,E)，关系代数表达式E1、E2、E3和E4，且如果严格按照表达式运算顺序，查询效率最高的是(36)。(36)

单选题下列标准代号中， (5) 为推荐性行业标准的代号。

单选题商业秘密是我国 (13) 保护的一项重要内容，它包括技术秘密和经营秘密两项基本内容。