Define transitive dependencies, Database Management System

Assignment Help:

What do you understand by transitive dependencies? Define with an example any two problems that can take place in the database if transitive dependencies are available in the database.

 Ans:  Assume X, Y, and Z are the set of attributes. If X → Y and Y → Z afterwards the functional dependency X → Z is a transitive functional dependency. Alternatively, if a nonkey attribute is as well functionally dependent on the other nonkey attribute(s), then there is a transitive functional dependency. Transitive functional dependencies are as well cause the data redundancies and the other consequences. For instance, consider the subsequent relation:

CREATE TABLE CONTACTS

(CONTACT_ID NUMBER (5) PRIMARY KEY,

 L_NAME   VARCHAR (20),

 F_NAME   VARCHAR (20),

 COMPANY_NAME VARCHAR (20),

 COMPANY_LOCATION VARCHAR (50))

 In the following relation, all the nonkey attributes are functionally dependent on the primary key, that is CONTACT_ID. But, there is as well a transitive functional dependency exists in the relation - CONTACT_ID  COMPANY_LOCATION because CONTACT_ID → COMPANY_NAME and COMPANY_NAME →COMPANY_LOCATION.  The result of transitive dependency, there are anomalies in the above relation like this:

  • Insertion Anomaly - A new company cannot be inserted till a contact person has been assigned to that company.
  • Deletion Anomaly - If a company has just only one contact person and is deleted from the table, we will lose the information about that company, as the company information is related with that person.
  • Update Anomaly - If a company changes its location we will should make the changes in all the records in which the company name appears.

Related Discussions:- Define transitive dependencies

Define seek time, Define seek time. The time for repositioning the arm ...

Define seek time. The time for repositioning the arm is known as the seek time and it enhances with the distance that the arm is known as the seek time.

Determine the objectives of object oriented design, Determine the Objective...

Determine the Objectives of object oriented design provide an overview of object oriented design; partitioning system to subsystems; describe how a software desig

Database Normalization, I have a homework assignment due today by midnight....

I have a homework assignment due today by midnight. I need help understanding databasse normalization and determining the type of form violation & how to fix the violation.

Determine the operation that do not participate to be union, 1. Which relat...

1. Which relational algebra operations do not need the participating tables to be union-compatible? Ans: Join is the relational algebra operations that do not need the particip

Determine the steps of path in association network, Determine the steps of ...

Determine the steps of path in association network You can analyse use of paths in association network in the following steps:  Examine every operation and see what asso

E-R, Mention various steps required to draw an E-R Diagram. Draw an E-R Dia...

Mention various steps required to draw an E-R Diagram. Draw an E-R Diagram for Student Information System. Mention all suitable assumptions to justify your answer.

Explain object oriented model, Explain Object oriented Model ? Object ...

Explain Object oriented Model ? Object Oriented Model - This model is based on the object-oriented programming language paradigm. It involves the features of OOP such as inhe

Explain saving derived attributes to avoid re-computation, Saving Derived A...

Saving Derived Attributes to Avoid Re-computation   As discussed, "redundancy means duplication of exact data". But, if multiple copies of same data are present in the system,

What are the various symbols used to draw an e-r diagram, What are the vari...

What are the various symbols used to draw an E-R diagram? Explain with the help of an example how weak entity sets are represented in an E-R diagram. Various symbols used to d

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd