Explain the exists and unique functions of sql, Database Management System

Assignment Help:

Explain the EXISTS and UNIQUE functions of SQL. Give an example for each?

EXISTS: The EXISTS function takes one parameter that is a SQL statement. If any records exist which match the criteria it returns true, or else it returns false. This provides you a clean, well-organized way to write a stored procedure in which does either an insert or update.

UNIQUE: If UNIQUE is particular then only unique values are used to compute the mean.


Related Discussions:- Explain the exists and unique functions of sql

Confirming.., I just purchased a document for you guys and wanted to confir...

I just purchased a document for you guys and wanted to confirm that it will be send within an hour or 2 to my email or where will document be sent to?

Distributed transaction atomic-consistent-isolated, A distributed transacti...

A distributed transaction consists of subtransactions that execute at different sites and access local DBMSs at those sites. For example, a distributed transaction that transfers m

What is online transaction processing, What is OLTP (Online Transaction Pro...

What is OLTP (Online Transaction Processing)? In OLTP - online transaction processing systems relational database design use the discipline of data modeling and generally follo

DBMS, what is specialization?

what is specialization?

What creates while a primary key is combined with a foreign, What it create...

What it creates while a primary key is combined with a foreign key? It creates Parent-Child relation ship between the tables that connect them while a primary key is combined w

Division operation, To do the division operation R1 ÷ R2, R2 should be a co...

To do the division operation R1 ÷ R2, R2 should be a correct subset of R1. In the following example R1 have attributes A and B and R2 have only attribute B so R2 is a correct subse

Example of transaction? , Example :; transfers transfer_amount from x's acc...

Example :; transfers transfer_amount from x's account to y's account ; Supposes x&y both accounts exist TRANSACTION (x, y, transfer_amount) Start transaction IF X AND Y

Objectives-file organisation in dbms, Objectives  After reading this un...

Objectives  After reading this unit you should be able to: Explain storage of databases on hard disks; Discuss the execution of various file Organisation techniques;

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