首页
登录
从业资格
The entity-relationship (E-R) data model
The entity-relationship (E-R) data model
题库
2022-08-02
29
问题
The entity-relationship (E-R) data model is based on a perception of a real world that consists of a clletion of basic objects, called( ) ,and of relationships among these objects.An entity is a“thing”or "object" in the real world that is distinguishable from other objects.Entities are described in a database by asetof(请作答此空) : A relationship isan association among several entities. The set of all entities of the same type and the set of all relationships of the ametype are termed an entity sct and relationship set, respectively. The overall logical structure (schema) of a database can be expressed graphically by an E-R diagram, which is built up from the fllowing components:( ) represent entity set,( ) represent atributes, ete. In addition to entities and relations, the E-R model represents certain( )to which thecontents of a database must conform. The entity-relationship model is widely used in database design.A.keysB.attributesC.recordsD.Rows
选项
A.keys
B.attributes
C.records
D.Rows
答案
B
解析
转载请注明原文地址:https://tihaiku.com/congyezige/2418649.html
本试题收录于:
中级 数据库系统工程师题库软件水平考试初中高级分类
中级 数据库系统工程师
软件水平考试初中高级
相关试题推荐
Theentity-relationship(E-R)datamodeli
Theentity-relationship(E-R)datamodel
Theentity-relationship(E-R)datamodel
Theentity-relationship(E-R)datamodel
Theentity-relationship(E-R)datamodel
Theentity-relationship(E-R)datamodel
随机试题
[img]2018m9s/ct_etoefz_etoeflistz_201808_0060[/img][br]Accordingtotheprofes
规模报酬递增和边际报酬递减是否可以同时存在?为什么?
患儿男,8个月。生后发现腰骶部中线处肿物,随年龄增长逐渐增大,肿物随患儿哭闹而有
患儿男,9岁,因水痘后2周,发热、头痛、双下肢麻木无力、大小便困难2天入院。查体
生用燥湿利水,炒用健脾止泻的药物是A:西洋参 B:白术 C:黄芪 D:人参
宜用土炒法炮制的药材是A:僵蚕B:枳壳C:苍术D:枳实E:白术
不属于细菌细胞质中重要成分的是A.核质B.胞浆颗粒C.质粒D.糖肽E.核蛋白体
共用题干 MoreThan8HoursSleepTooMucho
阅读材料: 材料1 英国著名历史学家、英国学术院院士霍布斯鲍姆指出,给确定某
对国有土地上被征收房屋价值的评估,应在()前进行。A.做出房屋征收决定 B.拟
最新回复
(
0
)