What is candidate key, Database Management System

Assignment Help:

What is Candidate Key

Super Key or Candidate Key: It is such an attribute of a table that can uniquely recognize a row in a table. Generally they have unique values and can never have NULL values. There can be more than one super key or candidate key in a table e.g. within a STUDENT table Roll and Mobile No. can both serve to uniquely recognize a student.

 


Related Discussions:- What is candidate key

What are the comparison operator in sql, What are the comparison operator i...

What are the comparison operator in SQL?  Comparison operator in SQL are =, LIKE and BETWEEN

#title using the invoice, using the invoice table shown below,write the rel...

using the invoice table shown below,write the relational schema,draw a dependencies,inclunding all partial and transitive dependencies.assume that the table does not contain repeat

In an e-r diagram how attributes are represented, In an E-R diagram how att...

In an E-R diagram how attributes are represented ? In an E-R diagram attributes are represented in a ellipse.

Increases efficiency-data fragmentation, Increases efficiency : Data is sto...

Increases efficiency : Data is stored close to most often used site, therefore retrieval would be faster. Also, data that is not required by local applications is not stored, there

Creating views with read only option-data control, Creating views with Read...

Creating views with Read only option : In the view definition this option is used to make sure that no DML operations can be done on the view.

What is the aim of object design, What is the aim of object design The ...

What is the aim of object design The aim of object design is to identify object which the system   contains and the interactions among them. The system implements specification

What three major types of actions includes databases, What three major type...

What three major types of actions includes databases? Briefly discuss these The three major types of actions including databases are: (i) Defining: It includes specifyin

Single-valued dependencies, Single-Valued Dependencies A database is a ...

Single-Valued Dependencies A database is a collection of related information and it is therefore inevitable that some items of information in the database would depend on some

Deletion anomalies-data redundancy, Deletion Anomalies: Loss of important ...

Deletion Anomalies: Loss of important Information: In some cases, useful information may be lost when a tuple is deleted. For instance, if we delete the tuple corresponding to stu

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