Differentiate between a unique key and a primary key, Database Management System

Assignment Help:

Differentiate between a unique key and a primary key.

- By default, clustered index on column are created by primary key while nonclustered index are created by unique key.

- Primary key doesn't allow NULLs however unique key allows one NULL.

 


Related Discussions:- Differentiate between a unique key and a primary key

I need web security expert, I need web security expert , website management...

I need web security expert , website management Project Description: i want professional for the below . website management server management database management

Define cascading rollback, Define Cascading rollback The phenomenon whe...

Define Cascading rollback The phenomenon where a single transaction failure leads to a series of transaction rollbacks is known as Cascading rollback.

Explain data abstraction, Explain data abstraction? Data abstraction Da...

Explain data abstraction? Data abstraction Data abstraction is a methodology in which enables us to isolate how a compound data object is utilized from the details of how it is

Give an expression within sql for queries, Consider the following relations...

Consider the following relations:  S (S#, SNAME, STATUS, CITY)  SP (S#, P#, QTY)  P (P#, PNAME, COLOR, WEIGHT, CITY) Give an expression within SQL for each of queries b

Explain instance and schemas, Explain Instance and schemas? Instances ...

Explain Instance and schemas? Instances and schemas: Databases changes over time as the information is deleted and inserted. The collection of information stored in database

Selective replication-data replication, Selective replication: This is a c...

Selective replication: This is a combination of generating small fragments of relation and replicating them rather than a entire relation. The data should be fragmented on require

List the drawbacks of relational database system, List the drawbacks of rel...

List the drawbacks of relational database system A) Repetition of data B) Inability to s certain information.

What is a candidate key, What is a candidate key? Minimal super keys ar...

What is a candidate key? Minimal super keys are known as candidate keys.

What are the advantages of logical databases, What are the advantages of Lo...

What are the advantages of Logical Databases? It offers a simple-to-use selection screens.  You can change the pre-generated selection screen to your needs.  It offers check f

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