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!
A distributed transaction consists of subtransactions that execute at different sites and access local DBMSs at those sites. For example, a distributed transaction that transfers money from a bank account at site A to a bank account at site B executes a subtransaction at A that does the withdrawal and then a subtransaction at B that does the deposit.
Such a distributed transaction must satisfy the ACID properties in a global sense: it must be globally atomic, isolated, consistent, and durable. The issue is, if the subtransactions at each site individually satisfy the ACID properties, does the distributed transaction necessarily satisfy the ACID properties? Certainly if the subtransactions at each site are individually durable, the distributed transaction is durable. Give examples of situations in which
(a) The subtransactions at each site are atomic, but the distributed transaction is not atomic.
(b) The subtransactions at each site are consistent, but the distributed transaction is not consistent.
(c) The subtransactions at each site are isolated, but the distributed transaction is not isolated.
explain concept of decomposition?
Question 1 What are the advantages of DBMS approach in managing data? Question 2 What are the services provided by a database system Question 3 List and briefly describe
What is the difference between serial and sequential files? How searching is applied on both? Ans: A serial file is one where the records have been stored in the order where
Horizontal Fragmentation- Horizontal fragmentation groups together the tuples in a relation that are collectively used by the main transactions. A horizontal fragment is produced b
What is a hashing function? What are the properties of a good hashing function? Describe the folding technique for hashing functions. Ans: Hashing function is a method
What is Gathering information and Producing ERD Gathering information: This could be a written document that explains the system in question with reasonable quantity of detai
Prove that a relation which is 4NF must be BCNF. Ans Let R be in 4NF. Suppose it is not in BCNF. Hence, there exists an FD X→Y in R such that x is not a super key. Although
Describe Parameteric end users? Parametric end users might be given update access, but are commonly not permitted to change the structure of data.
Question 1 Create a table student with attributes student name, roll number, total marks and percentage. Do the following operations Insert details in to the table Update
Define the Canonical cover Ans: A canonical cover F c for F is a set of dependencies like F logically implies all dependencies in F c , and F c logically entails all dependen
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