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?

NORRMALIZATION, Home based assignment Consider an ORDER table with the foll...

Home based assignment Consider an ORDER table with the following attributes: • Order Number (ONo),Customer Number (CNo),Customer Name (CNa),Item Number (INo),Unit Price (UP), Quant

Define a view and a trigger, Define a view and a trigger. Construct a view ...

Define a view and a trigger. Construct a view for the above relations that have the information about suppliers and the elements they supply. The view holds the S#, SNAME, P# , PNA

Design a gennalization and specialization hierarchy for an a, Design a genn...

Design a gennalization and specialization hierarchy for an automobile sales company

Super market, ..

Stored and derived attributes, Attributes that are directly kept in the dat...

Attributes that are directly kept in the data base. For example, 'Birth date' attribute of a person. Derived Attributes that are not stored directly but can be derived

Implementation of integrity rules, Question 1 Describe the following- ...

Question 1 Describe the following- Clustering Indexing Question 2 Explain the following with suitable real time examples- Implementation of Integrity rules

Develop a simple database of student records, In this programming assignmen...

In this programming assignment, you will develop a simple database of student records. Here are the requirements: 1) A student record contains a name and a number. We assume tha

Update operations in dbms - insert operation, Update Operations and Dealing...

Update Operations and Dealing with Constraint Violations There are three basic operations to be executes on relations: Insertion Deletion Update The INSER

Using literal character string-data manipulation language, Using Literal Ch...

Using Literal Character String Example: To print IS A as one string with column name employee SELECT ENAME || ' IS A ' || JOB AS "EMPLOYEE" FROM EMP;

What is primary key explain, What is primary Key Explain? Primary Key ...

What is primary Key Explain? Primary Key - Primary key is one of the candidate keys. It should be selected such in which its attribute values are never, or very rarely, chang

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages