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 DataWarehousing? Subject-oriented, meaning that the data in the database is organized so that all the data elements relating to the similar real-world event or object
For every n-ary relationship type R where n>2, we make a new table S to represent R. We contain as foreign key attributes in s the primary keys of the relations that show the parti
What are segments in oracle? Segments - Each table has single field of disk space, known as segment, set aside for it in the tablespace. Segments consist of contiguous sections
A Functional dependency is described by X Y between two groups of attributes Y and X that are subsets of R specifies a constraint on the possible tuple that can make a relation
What is magnetic disks?explain it? Magnetic disk provides the bulk of secondary storage of modern computer system. The disk capacity is growing at over 50% per year. But the st
Database Recovery And Security Introduction In this part we will introduce two main issues relating to database management systems. A computer system suffers from dissi
Objectives Define the terms RECOVERY and INTEGRITY; Define Recovery Techniques; Explain Error and Error detection techniques, and Define types of Authorisation.
What are the types of reference?explain it with suitable examples? Object oriented language given the ability to refer the object attribute of the type can be referred to the s
Indexed (Indexed Sequential) File Organisation It organises the file like a big dictionary, i.e., records are kept in order of the key but an index is stored which also allows
File Manager File manager handles the allocation of space on disk storage. It starts and maintains the list of structures and indices described in the internal schema that is
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