What is null described testing for null in sql?, Database Management System

Assignment Help:

What is NULL? Give an example to described testing for NULL in SQL?

The NULL SQL keyword is used to represent either a missing value or a value which is not applicable in a relational table. Consider there is a relation:

Person(id, name, address, phone)
Now to search ids and names of person who do not have a phone is:
Select id, name
from Person
where phone is null

Related Discussions:- What is null described testing for null in sql?

Explain the shadow paging recovery technique, Explain the shadow paging rec...

Explain the shadow paging recovery technique. Ans: Shadow paging is a method used to acquire atomic and durable transactions, and provides the capability to manipulate pages i

What is the role of order by clause, What is the role of ORDER By Clause? ...

What is the role of ORDER By Clause? ORDER BY clause: The ORDER BY clause permits you to sort the records in your result set. The ORDER BY clause can just be used in select s

What are the advantages of object oriented databases, What are the advantag...

What are the advantages of object oriented databases in comparison with others? Why it is still not widely used? Object oriented designs are coherent, efficient and less prone

Define a property that is not a property of transactions, Define a property...

Define a property that is not a property of transactions? Ans: Concurrency is not a property of transactions

Components of database manager, Components of database manager The ab...

Components of database manager The above functions are reached by the database manager. The major elements of a database manager are: Authorisation control: This mod

Php optimization on iis 8, Project Description: We have purchased facebo...

Project Description: We have purchased facebook style chat software which we are using with our site. It is prepared in PHP but the rest of the site is developed asp.net. Iss

Distinguish among a datareader class and a dataset class, Question (a) ...

Question (a) Concurrent access to data from a database is a normal part of application program usage. Describe three approaches to concurrency control (b) Distinguish among

Explain the timestamp ordering protocol, Timestamp Ordering Protocol A ...

Timestamp Ordering Protocol A timestamp is a tag that can be attached to any transaction or any data item, which indicates a specific time on which the transaction or data item

Vocabulary terms, imagery

imagery

Want massive amount of products imported through csv, OPENCART - Want Massi...

OPENCART - Want Massive amount of products Imported through CSV We have a massive list of products that would take completely too long to do data entry. We require a slick progr

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages