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

Describe the two alternatives for specifying structural, Describe the two a...

Describe the two alternatives for specifying structural constraints on relationship kinds? Relationship kinds have certain constraints in which limit the possible combination o

Selective replication-data replication, Selective replication: This is a c...

Selective replication: This is a combination of generating small fragments of relation and replicating them rather than a entire relation. The data should be fragmented on require

Assignment - 1 - redoing to improve grades, Assignment #1 Data Management ...

Assignment #1 Data Management The questions on this exam are based on the Baxter Aviation case scenario. 1. (5 points) The systems analyst proposes the following two relationshi

Decomposition properteis, what is lossless & dependency preserving decompo...

what is lossless & dependency preserving decomposition ?

Mis, explain various steps uses in evaluation and maintenance of MIS.

explain various steps uses in evaluation and maintenance of MIS.

Shared lock or read lock, Shared lock or Read Lock It is requested ...

Shared lock or Read Lock It is requested by a transaction that needs to just read the value of data item. A shared lock on a data item does not permit an exclusive lock

When is a transaction rolled back, When is a transaction rolled back? A...

When is a transaction rolled back? Any changes that the aborted transaction made to the database must be uncompleted. While the changes caused by an aborted transaction have be

What are called multilevel indices, What are called multilevel indices? ...

What are called multilevel indices? Indices with two or more levels are known as multilevel indices.

Er digrams, what is er digram given that example of hospital,bank and libra...

what is er digram given that example of hospital,bank and library er digram.

Differentiate sub-class and super-class, Differentiate sub-class and super-...

Differentiate sub-class and super-class? The specialization of a class is known as subclasses.eg: employee is a subclass of person and teller is a subclass of employee. Convers

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