What is functional dependency, Database Management System

Assignment Help:

 

A Functional dependency is described by X Y between two groups of attributes Y and X that are subsets of R specifies a constraint on the possible tuple that can make a relation state r of R. The constraint is for any two tuples t2 and t1 in r if t1[X] = t2[X] then they have t1[Y] = t2[Y]. This seems the value of X element of a tuple uniquely calculates the value of element Y.

 

 

1458_Functional Dependency.png


Related Discussions:- What is functional dependency

Non-redundant cover and canonical cover, Given the following set of functio...

Given the following set of functional dependencies {cf?bg, g?d, cdg?f, b?de, d?c} defined on R(b,c,d,e,f,g) a.Find a non-redundant cover. b.Find a canonical cover.

What is e-r model, What is E-R model? This data model is based on real ...

What is E-R model? This data model is based on real world that having of basic objects called entities and of relationship between these objects. Entities are explained in a da

Explain deadlock detection and recovery, Explain Deadlock detection and rec...

Explain Deadlock detection and recovery Deadlock Detection - A deadlock is said to take place when there is a circular chain of transaction, every waiting for the release of a

Need vmware technical support, Project Description: Critical Project for...

Project Description: Critical Project for VMware Technical support. VMWare ESXi 5.1 support for upgradation and migration problem. Technical expert of Vmware needed. Sk

Anomalies, define anomalies and different types of anomalies with example

define anomalies and different types of anomalies with example

Erd, Table_Name( attribute_1, attribute_2, attribute_3, ….. ,attribute_x) ...

Table_Name( attribute_1, attribute_2, attribute_3, ….. ,attribute_x) Primary Key ( attribute_1, attribute_2) Foreign Key attribute_4 References Table_Name_2 (repeat for each fore

Data redundancy, Data Redundancy -A lot of information is being repeated in...

Data Redundancy -A lot of information is being repeated in the relation. For instance, the information that MCS-014 is named SSAD is repetitive, address of Rahul is "D- 27, Main ro

Define the concept of design documentation, Design Documentation  The ...

Design Documentation  The Design Document shall be an extension of Requirements Analysis Design. "The Design Document will comprise a revised and much more detailed descrip

Data models, why older data models are being replaced by new data models....

why older data models are being replaced by new data models.

Relationship cardinality, Cardinality shows the number of instances of an e...

Cardinality shows the number of instances of an entity associated with another entity participating in a relationship. Depend on the cardinality binary relationship can be further

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