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

Represent the form as a relational schema, Question: This form represen...

Question: This form represents one of a number used for each sailing of a range of boats. A passenger may go on many sailings and will have the same passenger number for each.

What is hashing file organization, What is hashing file organization? ...

What is hashing file organization? In the hashing file organization, a hash function is computed on some attribute of every record. The result of the hash function specify in

Weak entity, Entity types that do not have any key attribute, and therefore...

Entity types that do not have any key attribute, and therefore cannot be identified independently, are known as weak entity types. A weak entity can be recognized uniquely only by

What is serializability, What is serializability? Explain its types? Th...

What is serializability? Explain its types? The data base system must control concurrent implementation of transactions, to ensure that the data base state remains consistent.

Discuss the mechanism to read data from and write to a disk, Discuss the me...

Discuss the mechanism to read data from and write to a disk? Disk read/write heads are mechanisms in which read data from or write data to disk drives. The heads have gone by

What is difference between primary index and secondary index, What is diffe...

What is difference between primary index and secondary index? Primary Index a) It is an ordered file whose records are of fixed length along with two fields. b) Only base

Discuss the problem of spurious tuples, Discuss the problem of Spurious tup...

Discuss the problem of Spurious tuples and how we may prevent it.    Ans:  A spurious tuple is, mainly, a record in a database that gets created while two tables are joined bad

Hashing, how to implement mid square hashing?

how to implement mid square hashing?

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