Question

Please read the following situation and construct an E-R diagram, using the concepts we learnt in class. We should use a computer graphing package, such as MS Powerpoint, to construct the E-R diagram, so it looks professional. Turn in a hard copy of the sketch at the due time. .

POP organization:

The POP (publish-or-perish) organization publishes several academic journals. They would like us to build them a database system, to help manage their business. As a first step, you interview 5 key users, and this is what we end up with after the interview.

Description of user requirements:

POP publishes a few hundred journals. A journal has a name, a chief editor, and several area editors. Each issue of a journal has a date and contains several articles. For example, the Journal of IS will have several issues, each one with an issue ID, starting from 1. Each article has a title, up to 10 authors, an area topic, and an abstract. POP interfaces heavily with the research community. All work at POP is done by members of the research community. Members of the research community have a name, an institution (no pun) to which they belong, an address, a phone number and up to 3 different research specialties.

A researcher can be a chief editor of up to 3 journals (all different of course), at any one time. In addition, a researcher can be an area editor of up to 8 journals. Chief editors and area editors of a journal are disjoint sets (the same person cannot both chief edit and area edit the same journal). Researchers also serve as reviewers for articles that have been submitted for review to a particular journal. All articles are written by researchers, and all articles are submitted for review to journals. A submitted article has a name, authors, an area topic, an abstract and from 2-4 reviewers. If it gets published, it becomes a published article, and appears in an issue of the journal to which it was submitted. If an article is submitted to multiple journals, it is treated as a separate submission (a new article) each time.

Reviewers for a particular journal are disjoint from the editors of that journal. A researcher cannot submit an article to a journal for which he/she is an editor, and also cannot review an article for which he/she is an author. Note that a researcher can be an editor as well as a reviewer, just not of the same journal. Similarly, researchers can be reviewers as well as authors, just not for the same article. Finally, researchers can be chief and area editors, just not of the same journal.

Note that the above description is designed to represent what we would get in the real world, if we worked as database analysts on a project. So, some parts of the description may not be “representable” in ER diagrams. This is what would happen in the real world too, since end-users do not know what can or cannot be represented in an ER diagram. What we need to do is capture as much information as we can in the ER diagram. In many cases, the same information can be represented in multiple ways in the ER diagram. The challenge is to find the “appropriate” representation concept in the ER diagram. This means that we should really explore the fine differences between the different concepts we learnt in class, and decide which is appropriate in each case.

Answer 1

E- Diaram EpITe i d JOURNAL SS ue ddh ARTICLE dt itta ea topic REVMEW 吣RLICED B ode fub.ha

Answer 2

Specialty-1 Specialty-2 Specialty-3 Reviewer-1 Reviewer 2 Area Topic Name Insttution Name Address Phone num Area Topic Abstract Tite Area Editor Article-1) Area Editor Cheif Editor (Article-2 Attnbute Date Chief Editor ssue ID Artcie-n) rea Editor Area Edilor Area Editor Editor Area Edito Area Editor Area Edilor belongs Area Editor Name Chief Editor Research Journal-1 Journal-2 Journal-4 Journal 6 Journal-7 Journal-8 Joumal-1

Note:

Here in this diagram only 8 journals are shown, the number of journals can be increase or decrease, but all the journals like journal-2, journal-3 will be having same attributes like journal-1.

Here only 2 reseachers are shown, the number of researchers can increase as per need. All the researchers will be having same attributes as researcher-2