Write a query to find name from the relational algebra, Database Management System

Assignment Help:

Consider the relations
City (city_name, state)
Hotel (name, address)
City_hotel (hotel_name, city_name, owner)

Answer the following queries in relational algebra
(i) Find out the names and address of hotels in Agra.
(ii) List the names of cities that have no hotel.
(iii) List the names of the hotels owned through ‘Taj Group'.

Ans: (i) Π name, address ( σ city_name= ‘Agra' (Hotelname=city_name City_hotel))
(ii) Π city_name (City) - Π city_name(City_hotel)
(iii) Π hotel_name ( σ owner='Taj Group' (City_hotel))


Related Discussions:- Write a query to find name from the relational algebra

Write short notes on relational model, Write short notes on relational mode...

Write short notes on relational model The relational model uses a collection of tables to show both data and the relationships between those data. The relational model is an ex

E-R MODEL, WHAT IS MEANT BY E-R MODEL

WHAT IS MEANT BY E-R MODEL

Discuss the types of integrity constraints with example, Discuss the types ...

Discuss the types of integrity constraints in which must be checked for the update operations - Insert and Delete. Give examples. Insert operation can violet any of the subse

advantages of database over file system, Q.   Why would you choose a datab...

Q.   Why would you choose a database system instead of simply storing data in operating system file? Define  at a base concept in details. Sol. Advantages of Database over Fil

Represent the form as a relational schema, Question: This form represen...

Question: This form represents one of a number used for each sailing of a range of boats. A passenger may go on many sailings and will have the same passenger number for each.

What is a virtual table that draws its data from the result, What is a virt...

What is a virtual table that draws its data from the result of an SQL SELECT statement? View is a virtual table that draws its data from the result of an SQL SELECT statement.

Describe the algorithm for updating indices, Describe the algorithm for upd...

Describe the algorithm for updating indices for a single level index when a record is    (i) Inserted  (ii)  deleted What will be the modification if there are multilevel in

Optimistic concurrency control, Optimistic Concurrency Control Is locki...

Optimistic Concurrency Control Is locking the only way to stop concurrency related problems? There exist some other ways too. One such way is known as an Optimistic Concurrency

Normalization, a project based on normalization with first, second and thir...

a project based on normalization with first, second and third normalization. There need to be a diagram also

Compare the two log based recovery schemes, Compare the two log-based recov...

Compare the two log-based recovery schemes in terms of ease of implementation and overhead cost.    Ans:  There are two types of log based recovery techniques: deferred update

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