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

What are the dbms languages, What are the DBMS languages? Briefly explain?...

What are the DBMS languages? Briefly explain? Data Definition language (DDL):A database schema is specified through a set of definitions expressed through a special language

Define deadlock prevention, Define Deadlock prevention These protocols...

Define Deadlock prevention These protocols make sure that the system will never enter a deadlock state. There are two methods to deadlock prevention. One approach makes sure t

Explain the data access protocol, (a) Explain the three types of potentia...

(a) Explain the three types of potential mistake which could occur if concurrency control is not properly enforced in the database system. Support your answer with appropriate ex

Develop a team database, I need a professional to prepare a database to co...

I need a professional to prepare a database to collect and store basic information. The information can be basic info such as contact details etc. One requirement i have is f

Describe interfaces for the dba, Describe Interfaces for the DBA? Inte...

Describe Interfaces for the DBA? Interfaces for the DBA - Most database systems holds privileged commands which could be used only through the DBA's staff. These involves com

Define cascading rollback, Define Cascading rollback The phenomenon whe...

Define Cascading rollback The phenomenon where a single transaction failure leads to a series of transaction rollbacks is known as Cascading rollback.

Rules of data normalisation, Rules Of Data Normalisation  Let us now su...

Rules Of Data Normalisation  Let us now summarise Normalisation with the help of various clean rules. The following are the necessary rules for the Normalisation process: 1.

Draw the precedence graph, Draw the precedence graph of the following sched...

Draw the precedence graph of the following schedule and determine whether the schedule is serializable. (Note that all instructions, except lock and unlock, are omitted. We assume

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