Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition

1
Exercises

• Apa saja komponen utama dari ER-Diagram ?
• Yang membuat sebuah entity unik adalah
• Sebutkan tipe dari attribut berikut
• Nama anak
• Jenis kelamin
• Jumlah anak
• Total discount
• Harga buku
• Pengarang buku
• Apa yang dibutuhkan untuk membuat rancangan
  logical database (ER-Diagram) ?
• Apakah yang dimaksud dengan weak entity ?
• Bagaimana membentuk key attribut dari weak entity
  ?

2
More Exercises

• In E-R modeling, entities within an entity class
  may have different attributes. T/F
• In E-R modeling, an attribute may be either
  composite or multi-value, but it cannot be both.
  T/F
• An identifier (key attribute) of an entity
  instance must consist of one and only one
  attribute. T/F
• The degree of a relationship is expressed as the
  relationships maximum cardinality. T/F
• Relationships among instances of a single entity
  class are called redundant relationships. T/F

3
A Bank Enterprise
4

• Sebutkan (nonweak) entity pada ERD tsb!
• Sebutkan (weak) entity pada ERD tsb jika ada!
• Sebutkan relasi yg ada serta tentukan batasan
  (min,max) nya!
• Sebutkan user requirement yg melandasi ERD tsb!
• Jika setiap customer harus punya satu account
  namun paling banyak dua pinjaman pada satu waktu
  dan setiap cabang tidak boleh punya lebih dari
  1000 pinjaman. Bagaimana hal ini dibuat dgn
  notasi (min,max)?

5

• A university database contains information about
  professors (identified by social, security
  number, or SSN) and courses (identified by
  courseid). Professors teach courses each of the
  following situations concerns the Teaches
  relationship set. For each situation, draw an ER
  diagram that describes it (assuming no further
  constraints hold).
• Professors can teach the same course in several
  semesters, and each offering must be recorded.
• Professors can teach the same course in several
  semesters, and only the most recent such offering
  needs to be recorded. (Assume this condition
  applies in all subsequent questions.)
• Every professor must teach some course.
• Every professor teaches exactly one course (no
  more, no less).
• Every professor teaches exactly one course (no
  more, no less), and every course must be taught
  by some professor.

6
Develop ER-Diagram based on following facts !

• Manufacturers have a name, which we may assume is
  unique, an address, and a phone number
• Product have a model number and a type (e.g.,
  television set). Each product is made by one
  manufacturer, and different manufacturers may
  have different products with the same model
  number. However, you may assume that no
  manufacturer would have two products with the
  same model number.
• Customers are identified by their unique social
  security number. They have email addresses, and
  physical addresses. Several customers may live
  at the same (physical) address, but we assume
  that no two customers have the same email
  address.
• An order has a unique order number, and a date.
  An order is placed by one customer. For each
  order, there are one or more products ordered,
  and there is a quantity for each product on the
  order.