What is the difference between a key and a superkey, Database Management System

Assignment Help:

What is the difference between a key and a superkey?

Key - A key a single attribute or a combination of two or more attributes of an entity set which is used to identify one or more examples (rows) of the set (table). It is a minimal combination of attributes.

Super Key - A super key is a set of one or more attributes in which, taken collectively, permits us to identify uniquely a tuple within the relation.


Related Discussions:- What is the difference between a key and a superkey

How to design a formal and exact model, How to design a formal and exact mo...

How to design a formal and exact model How to design a formal and exact model of real-world problems by applying findings of analysis phase of OMT. The object design phase find

Define access time, Define access time. Access time is the time from wh...

Define access time. Access time is the time from when a read or write request is issued to when data transfer starts.

State the object design for processing, State the Object Design for Process...

State the Object Design for Processing  The object design phase comes after analysis and system design phase. The object design phase includes implementation details like as i

What is first normal form, What is first normal form? The domain of att...

What is first normal form? The domain of attribute must contain only atomic (simple, indivisible) values.

Describe the objective of structural diagrams, Describe the objective of St...

Describe the objective of Structural Diagrams The main objective of structural diagram is to visualize, construct, specify and document static aspects of a system. Their eleme

Example on relational database schema, Question: The following relation...

Question: The following relational database schema corresponds to a part of a database used by the Registry Department of a university. DEPARTMENT (d#, d-name, head-of-dept)

What is known as heap file organization, What is known as heap file organiz...

What is known as heap file organization? In the heap file organization, any record can be placed anywhere in the file where there is space for the record. There is no ordering

Datamodels, explain thee diffrent types of data models

explain thee diffrent types of data models

Fds in relationships and teaches relationship, FDs in Relationships:  E...

FDs in Relationships:  Enrols Relationship: None as it is many to many Teaches Relationship : Course code → Instructor Instructor → Course code The next question is:

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