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

What is a built-in, What is a Built-in A notation of identity is built-...

What is a Built-in A notation of identity is built-into the data model or programming language and no user-supplied identifier is needed. This form of identity is used in objec

Using column aliases-data manipulation language, Using Column aliases E...

Using Column aliases Example: To print column names as NAME and ANNUAL SALARY SELECT ENAME "NAME", SAL*12 "ANNUAL SALARY" FROM EMP;

To delete a particular column in a relation which command, To delete a part...

To delete a particular column in a relation which command is used ? To delete a particular column in a relation ALTER command is used.

Define average latency time, Define average latency time. The average l...

Define average latency time. The average latency time of the disk is one-half the time for a full rotation of the disk.

Execute sql queries, Consider the relations described below: PHYSICIAN (re...

Consider the relations described below: PHYSICIAN (regno, name, telno, city) PATIENT (pname, street, city) VISIT (pname, regno, date_of_visit, fee) Where the regno and pname ide

Data control, Data Control The data control mostly refers to commands that...

Data Control The data control mostly refers to commands that permit system and data privileges to be passed to several users. These commands are usually available to database admi

Define the five basic operators of relational algebra, Define the five basi...

Define the five basic operators of relational algebra? Five basic operators of relational algebra are: 1. Union (∪∪∪∪) - Selects tuples which are in either P or Q or in both

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