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

DBMS, what is specialization?

what is specialization?

Serialisability, Serialisability: Any schedule that makes the similar resul...

Serialisability: Any schedule that makes the similar results as a serial schedule is known as a serialisable schedule. But how can a schedule are determined to be serialisable or n

Entity identifier key attributes, An entity type usually has an attribute w...

An entity type usually has an attribute whose values are distinct for every individual entity in the collection. Such an attribute is known as a key attribute and its values can be

multiple-mode locks, Multiple-mode locks : It offers two locks: exclusive ...

Multiple-mode locks : It offers two locks: exclusive locks and shared locks. But why do we require these two locks? There are a lot of transactions in the database system that neve

Discuss the concept of data independence, Question: a) Discuss the conc...

Question: a) Discuss the concept of data independence, explaining its importance in a database environment. b) To address the issue of data independence, the ANSI-SPARC t

Describe queries with complex types, Describe queries with complex types? ...

Describe queries with complex types? The present extension of the SQL query language deal with the complex type Let us start with the simple example: Find the title and t

ER-diagram, The State of NewYork certifies firefighters throughout state an...

The State of NewYork certifies firefighters throughout state and keep track all of them, as well as of the state’s fire departments. Each fire department has unique department numb

What is difference between truncate and delete, What is difference between ...

What is difference between TRUNCATE and DELETE? - Truncate can't be rolled back whereas Delete can be. - Truncate keeps the lock on table whereas Delete keeps the lock on ea

Using relational algebra which query finds customers, Using Relational Alge...

Using Relational Algebra which query finds customers, who have a balance of over 1000 ? Using Relational Algebra Π Customer_name( σ balance >1000(Deposit)) is query to find cu

What is a relationship called when it is maintained entities, What is a rel...

What is a relationship called when it is maintained between two entities? A relationship is called Binary relationship when it is maintained between two entities.

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