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?

Express the queries in relational algebra, Question: This question refe...

Question: This question refers to the database schema. a) Express the following queries in SQL: (i) Write the SQL code that will create the table Company. Your answer sh

Perform an exploratory analysis on the entire dataset, Australian Bureau of...

Australian Bureau of Statistics (ABS) provides retail data for different groups and different states as well as the aggregate numbers. Table 11 " Retail Turnover, State by Industry

Systems Analysis and design, Homework chapter 10 no 3

Homework chapter 10 no 3

State about the activity diagram, State about the Activity Diagram Act...

State about the Activity Diagram Activity diagrams show flow from one activity to other. It is an ongoing non atomic execution within a state machine. Activity finally results

Create a table student with attributes student name, Question 1 Create a t...

Question 1 Create a table student with attributes student name, roll number, total marks and percentage. Do the following operations Insert details in to the table Update

Differentiate between a subquery and a join, Differentiate between a subque...

Differentiate between a subquery and a join If we need to acquire information from one or more tables after that either subquery or join can be used. If the columns which are t

Decompose the table - 3nf or bcnf, Decompose the table with the following ...

Decompose the table with the following description and functional dependencies into a set of equivalent tables normalized to 3NF or BCNF. A long-standing international treaty am

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.

Apriori algorithm-find all frequent large itemsets, Your friend owns a comp...

Your friend owns a computer store in Yuen Long, selling Desktop and Notebook PCs and other computer peripherals. Having been rather successful with his business there, he decided t

Object-based models - data models, Object-based Models: Use objects as key ...

Object-based Models: Use objects as key data representation components . Examples:- Entity-Relationship Model: It is a collection of real world objects known as entitie

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages