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!
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
what are the main characteristics of database
What are the DBMS languages? Explain. Ans: a) Data Definition Languages (DDL): It is employed to specify database schema for example CREATE DROP statements etc. b) Dat
How to create values of structured type? Constructor functions are used to make values of structured types. A function with the similar name as a structured type is a construct
In E-R Diagram how derived attribute are represented ? In E-R Diagram By Dashed ellipse derived attribute are represented.
Explain the cartesian product in Database Management System
The following variant of the primary copy asynchronous-update replication protocol has been proposed for totally replicated systems. (a) A transaction executing at site A updat
What are the advantages and disadvantages of merging an association into a class? Advantages: i) Less number of tables ii) Faster performance due to the fewer tables
What are the disadvantages of relational approach? Disadvantages of relational approach: • Substantial hardware and system software overhead • May not fit all business models •
In order to keep pace with competitors, Space Ltd has decided to implement an ERP system in order to replace its old legacy and manual systems. Management does not have much knowle
Show, with the help of an example, that relatively high-level transitions result when system or program is stimulated by the outside events. In diagram below, we can observe i
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