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!
Define physical and logical data independence. How does this architecture help in achieving these?
Data independence entails that change in one view must not need a change in the view(s) above. There are two sorts of data independence: logical and physical. The meaning of Logical data independence is that the conceptual view can be changed without influencing the existing external view, that is a given record may be spilt or combined along with other records but the external views need not be modified to reflect this. The meaning of Physical data independence is that the physical storage structures or devices employed to store the data can be changed without effecting the existing conceptual view or external view, that is if earlier indexed sequential files are employed to store data and then the B- trees are used, even then the upper layers must not be effected.
Explain Two phase locking protocol A transaction is consider as to follow the two-phase locking protocol if all locking operations precede the first unlock operation in the tra
Define instance and schema? Instance: Collection of data stored in the data base at a certain moment is Schema: The overall design of the data base is known as the data base
Question: (a) Define the term e-Government and briefly explain, using appropriate examples, the aspects it covers. (b) Give four reasons as to why a country should adopt e
Column Constraints: NOT NULL, UNIQUE, CHECK, PRIMARY KEY, DEFAULT, REFERENCES, On delete Cascade : Using this key whenever a parent row is removed in a referenced
Define the Two Phase Locking Protocol This is a protocol that is used to make sure serializability of transactions. This protocol needs that every transaction issue lock and u
These are the binary operations; i.e., each is applied to two relations or sets. These two relations can be union compatible excluding in case of Cartesian product. Two relations R
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
How many levels can be viewed in Architecture of the database ? Architecture of the database can be viewed as three levels.
read-set(T) : Each data items that are read by a transaction T Timestamps : for all transaction T, the start-time and the end time are reserved for all the three phases.
Haw does it work one database application
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