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!
When are two schedules said to be view equivalent?
Ans: Two schedules that is denoted as S and S' are said to be view equivalent if the subsequent three conditions are met
1) For every data item Q, if a transaction Ti reads the initial value of Q in schedule S, after that transaction Ti should in schedule S' also read the initial value of Q.
2) For every data item Q, if a transaction Ti executes read(Q) in schedule S and that value was generated by Tj (if any) , then transaction Ti must in schedule S' as well read the value of Q generated by Tj.
3) For every data item Q, if a transaction if any that carries out the final write(Q) in schedule S should perform the final write(Q) in schedule S'.
Problem: You are given the following schema 1. Flights(flno, from, to, distance) 2. Aircraft(aid, flno, aname, cruisingRange) 3. Certified(eid, aid) 4. Employees(eid, ena
Explain DML with some examples? DML - Data Manipulation Language: statements used for managing data within schema objects. Some examples: • SELECT - retrieve data from the a da
Explain Object oriented Model ? Object Oriented Model - This model is based on the object-oriented programming language paradigm. It involves the features of OOP such as inhe
Critically explained the benefits and limitations of different database technologies with proper examples
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 sma
A relation has: Relational Schema Relation instance Relational Schema: A relational schema shows the relation's name, its attributes and the domain of every a
Describe logical data independence ? Logical Data Independence - It is the capacity to modify the conceptual schema without having to change external schemas or application p
Breaking into Subsystems Decomposition is a significant technique for coping with complexity based on idea of divide and conquers. In dividing a problem into sub problems, the
Explain Candidate Key and Super Key A super key is a set of one or more than attributes that, taken collectively, permits us to identify uniquely a tuple in the relation. Wher
Explain briefly concurrent task by taking an example. Concurrent Task- The concurrent occurrence of more than one event is called concurrent task. Operating systems can handl
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