In an E-R diagram attributes are represented by -
Ellipse
For instance, if you have an Entity "Student" (in a rectangle), its attributes "Student ID", "Name", and "Major" would each be drawn in an oval (ellipse) and connected to the "Student" rectangle with a line.
Important Questions from ER Model
______ are some problems that can occur when creating an entity-relationship model.
Relations produced from E - R Model will always be in ______
Consider the following statements:
Statement I: Composite attributes cannot be divided into smaller subparts.
Statement II: Complex attribute is formed by nesting composite attributes and multi- valued attributes in an arbitrary way.
Statement III: A derived attribute is an attribute whose values are computed from other attribute.
Which of the following is correct?
A company is consuming parts in the manufacturing of other products. Each of the part is either manufactured within the company or purchased from the external suppliers or both. For each part, partnumber, partname is maintained. Attribute batchnumber is maintained if the consumed part is manufactured in the company. If part is purchased from external supplier, then supplier name is maintained. Which of the following constraints need to be considered when modelling class/subclass concepts in ERD for the given problem.
Which of the following key constraints is required for functioning of foreign key in the context of relational database?
