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!
Transactions And Concurrency Management
Introduction
One of the main benefits of storing data in an integrated repository or a database is to permit sharing of it between multiple users. Various users access the database or perform transactions at the similar time. What if a user's transactions try to access a data item that is being used /modified by another transaction? This unit attempts to give details on how concurrent transactions are implemented under the control of DBMS. Though, in order to describe the concurrent transactions, first we must explain the term transaction.
Concurrent implementation of user programs is essential for good performance of DBMS, as concurrent running of various user programs keeps utilizing CPU time efficiently, as disk accesses are frequent and are relatively slow in case of DBMS. Also, a user's program may carry out a lot of operations on the data returned from DB, but DBMS is only concerned about what data is being written from / read / into the database.
What is meant by computing the closure of a set of functional dependency? The closure of F denoted by F + is the set of functional dependencies logically implied by F.
Explain Growing Phase of locking Growing Phase: In this phase the transaction can only obtain locks, but cannot release any lock. The transaction enters the growing phase as so
Probelm: (a) A distributed database (DDB) is a collection of multiple, logically interrelated databases which are physically distributed over a computer network" (i) Give a
Describe the tools that are available for managing MySQL Server. Given below are the tools to manage MySQL server: mysqld - MySQL server daemon. This is used to begain t
What is an Index? An index is a small table having only two columns. The first column has a copy of the primary or candidate key of a table and the second column having a set o
The scenario You have been approached to design and implement a prototype of a distributed information system for a national car part retail outlet chain. The company comprises
What are referential integrity constraints? A value that appears in single relation for a given set of attributes also appears for a particular set of attributes in another rel
Database Administrator One of the main perpose for having the database management system is to have control of both data or programs accessing that data. The person having li
Explain weak and strong entity type ? Weak and Strong entity type: An entity set which does not have a primary key is referred to as a weak entity set. The existence of a wea
Attributes attached to an entity can be of various types. Simple The attribute that cannot be further separated into smaller parts and shows the basic meaning is known as a
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