Super keys, Database Management System

Assignment Help:

A super key is an attribute or set of attributes used to recognize the records uniquely in a relation.

For instance, in the Relation PERSON defines earlier PERSON_ID is a super key since PERSON_ID is unique for every person. Likewise (PERSON_ID, AGE) and (PERSON_ID, NAME) are also super keys of the relation PERSON as their combination is also unique for each record.


Related Discussions:- Super keys

Create student db and retrieve all student name in cs, Create a Student dat...

Create a Student database and Retrieve the names of all students majoring in ‘CS' Consider the following relational database: STUDENT (name, student#, class, major) COURSE (co

Record based logical models, Record based Logical Models: Use records as th...

Record based Logical Models: Use records as the key data representation components Examples: Relational Model: It shows data as well as relationship between data in the form

E - r schema with weak entity, Consider the E/R schema with weak entity set...

Consider the E/R schema with weak entity sets shown below. Come up with the SQL CREATE TABLE statements (with appropriate primary key, unique and foreign key constraints). Include

2phase locking, we need example of 2phase locking

we need example of 2phase locking

The average amount of their orders , Make SQL statements for the following ...

Make SQL statements for the following scenarios. Your response should contain SQL statement, output and any other assumptions you have made to arrive at the answer. For Colorado cu

Fragmentation, let us consider a table having 2200 records and the fixed si...

let us consider a table having 2200 records and the fixed size of the table to be considered as 25.then how many numbers of table is requredto perform horizontal fragmentation

Produce a set of relations - normalisation, Produce a set of relations (equ...

Produce a set of relations (equivalent to the Finkelstein entity list) in third normal form (3NF) from the following un-normalised relation. You must use the Finkelstein methodolog

Hoework, Farmer Bob, Farmer Jane and Farmer Jose run a cow farming co-op. ...

Farmer Bob, Farmer Jane and Farmer Jose run a cow farming co-op. For every cow they keep the cow’s name, age (or date of birth), breed and numbered plastic ear tag. The each of t

E r diagram, how to make an e r diagram?

how to make an e r diagram?

Stored and derived attributes, Attributes that are directly kept in the dat...

Attributes that are directly kept in the data base. For example, 'Birth date' attribute of a person.   Derived  Attributes that are not stored directly but can be derived

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