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?

Relational database implementation, You must implement the entity relations...

You must implement the entity relationship model provided in the model solution to Assignment 1. The model solution will be released on the course website approximately TWO (2) we

Remove partial dependancy, , write the relational schema, and draw the new ...

, write the relational schema, and draw the new dependency diagrams. Identify the normal forms for each table structure you created

Mobile database, write short note on mobile database

write short note on mobile database

Mappings between levels and data independence, Mappings between Levels and ...

Mappings between Levels and Data Independence The 3 levels of abstraction in the database do not exist separately of each other. There must be some correspondence, or mapping

Data Warehousing Job Scheduling, 1) Define a job scheduling strategy that w...

1) Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pict

Er diagram, a publishing company produce scientific books on various subjec...

a publishing company produce scientific books on various subjects. the books are written by authors who specialize in one particular subject. the company employs editors who, not n

Relational constraints, Relational and E-R Model There are three types o...

Relational and E-R Model There are three types of constraints on relational database that have: DOMAIN CONSTRAINT PRIMARY KEY CONSTRAINT INTEGRITY CONSTRAINT

Define access time, Define access time. Access time is the time from wh...

Define access time. Access time is the time from when a read or write request is issued to when data transfer starts.

A step-wise distributed database design methodology, A step-wise distribute...

A step-wise distributed database design methodology Following is a step-wise methodology for distributed database design. (1) Examine the nature of distribution. Find out wh

Data envelopment analysis , I need a help with my assignment of data envelo...

I need a help with my assignment of data envelopment analysis which is due for submission next week on monday the 10th Dec. Will you be able to help so that I can submit it on tim

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages