Execute sql queries, Database Management System

Assignment Help:

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 identify the physician and the patient uniquely corresponding. Express queries (i) to (iii) in SQL.
(i) Get the name and regno of physicians who are in Delhi.
(ii) Find out the name and city of patient(s) who visited a physician on 31 August 2004.
(iii) Get the name of the physician and the total number of patients who have visited her.
(iv) What does the subsequent SQL query answer
SELECT DISTINCT name
FROM PHYSICIAN P
WHERE NOT EXISTS
( SELECT *
FROM VISIT
WHERE regno = p.regno )

(i) Select name, regno from PHYSICIAN where city = ‘Delhi';
(ii) Select pname, city from PATIENT,VISIT where PATIENT.pname=VISIT.pname and date_of_visit = '31-Aug-04';
(iii) select name, count(*) from PHYSICIAN, VISIT where PHYSICIAN.regno = VISIT.regno group by Physician . regno;
(iv) This will provide the name of physicians who have not visited any patient.


Related Discussions:- Execute sql queries

Describe participation constraints, Describe Participation Constraints? ...

Describe Participation Constraints? Participation Constraints - The participation constraint exacts whether the existence of an entity depends on its being related to another

What are the time stamps associated with each data item, What are the time ...

What are the time stamps associated with each data item? W-timestamp (Q) denotes the largest time stamp if any transaction that implemented WRITE (Q) successfully. R-timesta

Describe the storage structure of indexed sequential file, Describe the sto...

Describe the storage structure of indexed sequential files and their access method. Ans: Index offers a lookup capability to rapidly reach the vicinity of the desired record.

The extract statement do in extract datasets, What does the extract stateme...

What does the extract statement do in extract datasets? The data is written to virtual memory by extract commands.

Synonyms and indexes, Synonyms and Indexes Some of the essential proper...

Synonyms and Indexes Some of the essential properties of indexes are: An Index is a schema Object Indexes can be formed explicitly or automatically Indexes are m

What are the basic objects of the data dictionary, What are the basic objec...

What are the basic objects of the data dictionary? Tables Domains Data elements Structures Foreign Keys

DBMS, You are managing the following database system: • DBMS: Oracle 11g...

You are managing the following database system: • DBMS: Oracle 11g • OS: Sun Solaris • System architecture: Web-based application using ASP.Net • Purpose of Server: HR manage

What is an index as defined in oracle, Normal 0 false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

What is horizontal fragmentation, What is horizontal fragmentation? Hor...

What is horizontal fragmentation? Horizontal fragmentation divides the relation by assuming every tuple of r to one or more fragments

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