What is aggregate function, Database Management System

Assignment Help:

What is aggregate function? Briefly describe it?

Aggregate functions are functions that take a collection of values as input and return a one value. SQL offers 5 built-in aggregate functions:

a)      Average: avg

b)      Minimum:min

c)       Maximum: max

d)      Total:sum

e)      Count:count

Average: avg

Select avg (balance)

From account

Where branch-name='perryridge'

Count :count

Select branch-name,count(distinct customer-name)

From depositior,account

Where depositor.account-number=account.account-number

groupby branch-name

 


Related Discussions:- What is aggregate function

Explain data abstraction, Explain data abstraction? Data abstraction Da...

Explain data abstraction? Data abstraction Data abstraction is a methodology in which enables us to isolate how a compound data object is utilized from the details of how it is

Define the attribute inheritance, Define the Attribute Inheritance The ...

Define the Attribute Inheritance The attributes of a higher level entity set are inherited through a lower level entity set made by specialization-generalization hierarchy. Nam

Fragmentation, let us consider a table having 2200 records and the fixed si...

let us consider a table having 2200 records and the fixed size of the table to be considered as 25.then how many numbers of table is requredto perform horizontal fragmentation

What is the difference between a key and a superkey, What is the difference...

What is the difference between a key and a superkey? Key - A key a single attribute or a combination of two or more attributes of an entity set which is used to identify one

What is an e-r model and draw an e-r diagram for the company, What is an E-...

What is an E-R model? Draw an E-R Diagram for the company database with following Descriptions? The company is organized within departments. Each department has a unique name a

Aggregation, What does Aggregation mean?

What does Aggregation mean?

Relational DB, Suppose R is a relation with attributes A1, A2,..., An. As a...

Suppose R is a relation with attributes A1, A2,..., An. As a function of n, tell how many superkeys R has, if: 1.1 The only key is A1. 1.2 The only key is A1 and A2. 1.3 The o

What do you understand by a view, What do you understand by a view? What do...

What do you understand by a view? What does WITH CHECK OPTION clause for a view do? - A view is a virtual table which comprises fields from one or more real tables. - It is

Exclusive lock, Exclusive lock It is asked for by a transaction on...

Exclusive lock It is asked for by a transaction on a data item that it wants to update. No other transaction can put either a shared lock or an exclusive lock on a dat

ER Diagram, Soccer player ER Diagram to Relational database schema

Soccer player ER Diagram to Relational database schema

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