Define partial key and primary key, Database Management System

Assignment Help:

Define Partial Key and Primary Key

A partial key, also known as discriminator, is the set of attributes which can uniquely identify weak entities that are related to similar owner entity. Primary key is a unique key but not comprise null values. An entity set can comprise at most one primary key.


Related Discussions:- Define partial key and primary key

Write short notes on schema diagram, Write short notes on Schema diagram.  ...

Write short notes on Schema diagram.  A database schema along with primary key and foreign key dependencies can be depicted pictorially by schema  diagram. Every relation appea

What is an index, What is an index? An index is a structure that helps ...

What is an index? An index is a structure that helps to place desired records of a relation quickly, without probing all records.

Create table, What are the advantages of creating a table from existing tab...

What are the advantages of creating a table from existing table?

Define shadow paging, Define shadow paging. An alternative to log-based...

Define shadow paging. An alternative to log-based crash recovery method is shadow paging. This technique requires fewer disk accesses than do the log-based methods.

Define atomicity and aggregation, Atomicity : Either all functions are lai...

Atomicity : Either all functions are laid out or none are. Users could not have to think about the effect of incomplete operations. DBMS ensures this by undoing the functions

Consistency, what do you mean by consistency in rdbms?

what do you mean by consistency in rdbms?

Keys, #questiontypes of keys examples..

#questiontypes of keys examples..

Create database for car application, The Database MySQL scripts cars_f...

The Database MySQL scripts cars_for_sale.sql and car_details.sql containing the data to use for this task have been supplied. To complete this task, you need to first create

Deadlock prevention, Deadlock Prevention One of the easiest approaches ...

Deadlock Prevention One of the easiest approaches for avoiding a deadlock would be to obtain all the locks at the begin of the transaction. Though, this approach restricts conc

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