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Construct an E-R model for the below assumption and find out the degree of the relationship :-

A technician uses exactly one notebook for each project.Each notebook belongs to one technician for each project.Note that a technician may still work on many projects and maintain different notebooks for different projects

(a) Unary

(b) Binary

( c ) Ternary

(d) Two binary relations

 

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2 Answers

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I think it is Binary because between technician and notebook it is 1-1 but in project it is many.So it is basically 1-M relationship.So I think it is binary.
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Based on the scenario you've provided, we have three entities: Technician, Notebook, and Project.

  • A Technician uses exactly one Notebook for each Project.
  • Each Notebook belongs to one Technician for each Project.
  • A Technician may work on many Projects and maintain different Notebooks for different Projects.

This scenario describes a ternary relationship because it involves three entities that are all interrelated. The degree of the relationship is therefore 3 (ternary).

Here's a simplified way to visualize the E-R model:

Technician ----uses----> Notebook ----for----> Project
    ^                                            |
    |                                            |
    |------------------maintains-----------------|

In this model:

  • The 'uses' relationship connects Technician and Notebook.
  • The 'for' relationship connects Notebook and Project.
  • The 'maintains' relationship connects Technician and Project.

All three entities are interconnected, creating a ternary relationship.

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