Define views in relational algebra, Database Management System

Assignment Help:

Views in relational algebra: 

 1. Basic expression contains either 

a) A relation in the database.

b) A constant relation.

2.  General expressions are madde out of smaller sub expressions using 

a) σp(E1) select (p a predicate) 

b) ∏s(E1) project (s a list of attributes) 

c) Px(E1)rename (x a relation name) 

d) E1∪E2 union

e) E1- E2 set difference 

f) E1x x E2 cartesian product


Related Discussions:- Define views in relational algebra

Explain the dynamic hashing techniques, Explain the Dynamic Hashing Techniq...

Explain the Dynamic Hashing Techniques There are two methods in it: extendible hashing - stores an access structure in addition to the file, and therefore is somewhat identica

Describe second normal and third normal form, Database Management Systems ...

Database Management Systems 1. Explain SQL Server 2000 Architecture with diagram. 2. Describe Second Normal and Third Normal Form. 3. Explain about query engine and stora

Er diatgrams, Ask q“A database will be made to store information about pati...

Ask q“A database will be made to store information about patients in a hospital. On arrival, each patient’s personal details (name, address, and telephone number) are recorded wher

What are the several kinds of the update operations relation, What are the ...

What are the several kinds of the update operations on relations? Also explain the constraints on these update operation. Give instance in support of your answer. There are th

Large Project, Can you help me with the following: Drop statements for all...

Can you help me with the following: Drop statements for all objects in the lab project. Create statements for all objects of the lab project Create indexes for foreign keys Cre

Explain recursive relationship type, Explain Recursive relationship type? ...

Explain Recursive relationship type? Recursive relationship type: A recursive relationship is one in that the similar entity participates more than once in the relationship

Heap files (unordered file), Heap files (unordered file) Mostly these f...

Heap files (unordered file) Mostly these files are unordered files. It is the easiest and most basic type. These files having of randomly ordered records. The records will have

Determine the term- active values, Determine the term- Active values An...

Determine the term- Active values An active value is that has dependent values. Every dependent value registers itself with active value that contains a set of dependent values

Define data conversion, Define data conversion? Helpful to load data in...

Define data conversion? Helpful to load data into temporary staging tables. Then can write SQL code to do much of data processing. SQL code is simpler and faster to write than

Draw an e-r diagram and convert it to a relational schema, In an organizati...

In an organization several projects are undertaken. Each project can employ one or more employees. Each employee can work on one or more projects. Each project is undertaken on the

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