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!
Serialisable Schedules:If the processes of two transactions conflict with each other, how to verify that no concurrency related problems have happened? For this, serialisability theory has been developed. Serialisability theory attempts to verify the correctness of the schedules. The rule of this theory is:
"A schedule S of n transactions is serialisable if it is equal to some serial schedule of the similar 'n' transactions".
A serial schedule is a schedule in which either transaction T1 is totally done before T2 or transaction T2 is totally done before T1. For instance, the following figure clears the two possible serial schedules of transactions T1 & T2.
Schedule A: T2 followed by T1
Schedule B: T1 followed by T2
Schedule
T1
T2
Read X
Read Y
Subtract 100
Display X+Y
Write X
Add 100
Write Y
Figure: Serial Schedule of two transactions
Schedule C: An Interleaved Schedule
Figure: An Interleaved Schedule
Now, we have to figure out whether this interleaved schedule would be performing read and write in the same order as that of a serial schedule. If it does, then it is equivalent to a serial schedule, otherwise not. In case it is not equivalent to a serial schedule, then it may result in problems due to concurrent transactions.
1. Explain different addressing modes of 8086 Explanation of all addressing modes 2. Write a sequence of instructions to exchange two register contents using stack
Define the terms 1) physical schema 2) logical schema. Physical schema: The physical schema explains the database design at the physical level, which is the lowest level of abs
Introductory course and so does not require any fancy coding. I will provide a guidance document to help you in producing the solutions.
Describe Physical Data independence ? Physical Data Independence - It is capacity to modify the internal schema without having to change conceptual schema. Therefore, the exter
What is Natural Language Interfaces? Natural Language Interfaces - These interfaces accept requests written within English or a few other language and attempt to "understand" t
external view of DBMS in healthcare department?
What are two special events? The two special events are as "entry" and "exit". Any action which is marked as linked to entry event is executed whenever given state is entered v
1. Determine the set of minimal functional dependencies for the following data. The local bakery, Happy Cakes, needs your help designing a database that will support a kiosk in
Logical Operators Rules of Precedence: Order evaluated Operator 1 All comparison operators 2
Define the concept of generalization A generalization is relationship between specific kind of thing and general thing. It is also known as "is-a-kind-of" relationship. Inher
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