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!
What are the General Transformation Rules for Relational operations?
Ans: The transformation rules transform one relational algebra expression to AN
EQUIVALENT ONE
1. Employed by the query optimizer to optimize query tree
2. Any type of rule, if applied, ensures that the resultant tree is equivalent → resulting execution plan is equivalent
General Transformation Rules is as follow:
1. Commutativity of s: The s operation is commutative:
Consider an information system designed for an online company which provides IT products and services These include desktops, laptops, networking products, IT books, parts, and
What are the types of storage devices? Primary storage Secondary storage Tertiary storage Volatile storage Nonvolatile storage
Explain the challenges before an E-business management.
Use of partial data by applications : In common, applications work with views rather than whole relations. Thus, it may be more appropriate to work with subsets of relations rather
What are the parts of SQL language? The SQL language has various parts: data - definitition language Data manipulation language View definition Transaction contr
One-way Associations When an association is traversed only in the one direction, then it is implemented as a pointer i.e.an attribute which contains an object reference. If mu
Removing a Synonym: DROP SYNONYM D30;
Describe the four main ways of optimising disk block access. Ans: a. Disk b. Non-volatile writes buffers c. File organization (Clustering) d. Log-based file system
Describe Specialsation and generalization? Specialisation /generalization: This is a top down and bottom up approach to the design of database. It displays the IS_A relation
What is banker's algorithm? Banker's algorithm is a deadlock avoidance algorithm that is applicable to a resource-allocation system with multiple instances of each resource ty
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