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!
The following variant of the primary copy asynchronous-update replication protocol has been proposed for totally replicated systems.
(a) A transaction executing at site A updates only the replicas at A before it commits (it needed to access no other site since replication is total).
(b) After the transaction commits, a second transaction is initiated to update the primary copies of all items updated at A.
(c) After the transaction in step (b) has completed, each primary site propagates the update made at that site to all secondaries (including the one at site A). Updates made to a primary copy by several transactions are propagated to secondaries in the order in which the primary was updated.
Explain why, in step (b), all primaries must be updated in a single transaction and, in step (c), the update is propagated to site A.
Describe analysis of access paths To describe analysis of access paths, consider an example of the design of a company's employee skills database. A part of the object model fr
What is a virtual table that draws its data from the result of an SQL SELECT statement? View is a virtual table that draws its data from the result of an SQL SELECT statement.
In which format database schema is written ? Data base schema is written in the DDL format.
Adding Redundant Associations for Efficient Access The expression redundant association means using "duplicate association for proficient access". While analysis, it is not a
Explain how the object classes are mapped to tables. Each object class maps to one or more than one tables in the database. The objects in the class may be partitioned horizont
Draw an EER diagram that captures the "is-a" hierarchy of students in another simple database. The database captures both the "basic" information (say, student ID and student name)
What is meant by buffer blocks and disk buffer The blocks residing temporarily in main memory are referred to as buffer blocks. The area of memory where blocks reside t
Define What are the desirable properties of a decomposition Ans: What are the desirable properties of decomposition - dependency preserving. Because Lossless join and dependen
Describe the two alternatives for specifying structural constraints on relationship kinds? Relationship kinds have certain constraints in which limit the possible combination o
WHAT IS SQL
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