Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
In a relation, tuples are not inserted in any definite order. Ordering of tuples is not defined as a part of a relation definition. Though, records may be structured later according to some attribute value in the storage systems. For instance, records in PERSON table may be structured according to PERSON_ID. Such organisation or data depends on the requirement of the underlying database application. Though, for the purpose of display we may get them displayed in the sorted order of age. The following table is sorted by age. It is also worth states here that relational model does not permit duplicate tuples
PERSON
PERSON_ID NAME AGE ADDRESS
2 Sharad Gupta 33 Pocket 2, Mayur Vihar.
1 Sanjay Prasad 35 b-4,Modi Nagar
3 Vibhu Datt 36 c-2, New Delhi
Super Keys, Candidate Keys and Primary Keys for the Relations
As discussed in the last section ordering of relations does not matter and all tuples in a relation are unique. Though, can we uniquely recognize a tuple in a relation? Let us talk about the concepts of keys that are primarily used for the purpose as above.
Explain sorted File with advantages? Sorted file The sort utility shall perform one of the subsequent functions: 1.Sort lines of all the named files together and write the
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.
Define database management system? Database management system (DBMS) is a set of interrelated data and a combination of programs to access those data.
The basic merits of decomposition. The Advantages of Decomposition 1. Separate person can work on each subsystem. 2. A particular software engineer can specialize in a
Prepare a gantt chart for the stock control project: Scenario Lucas-TVS is the Leader in Auto Electricals in India today with 50 years experience in desig
Unrepeatable reads : Assume T7 reads X twice during its implementation. If it did not update X itself it could be very disturbing to see a dissimilar value of X in its next read. B
atient(PNumber, Name, NHS_no, Amount_due, DNO, Doctor, Medical_Treatment), relation of schema Staff(StaffNum, Name, DNO, Task) and relation of schema Dept(DNO, Name, Location, Dire
Explain mechanism of nested queries? SQL gives a mechanism for nesting subqueries. A subquery is a select from where expression that is nested within one more query. A common u
Define upgrade and downgrade? It gives a mechanism for conversion from shared lock to exclusive lock is called as upgrade. It gives a mechanism for conversion from exclusive
I want to fragment existing table using java code... help me..!!
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd