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 Deadlock avoidance
These protocols as well ensure that the system will never enter a deadlock state although the way it is done is different from deadlock prevention. In this way whenever a transaction requests for some data, the system refer the resources currently allocated to each procedure and the future requests and releases of each process currently allocated to each procedures and the future requests and releases of every process, to decide whether the current request can be satisfied or should wait to prevent a possible future deadlock. In this the transactions must give additional information about how in future the data will be requested.
Exclusive lock It is asked for by a transaction on a data item that it wants to update. No other transaction can put either a shared lock or an exclusive lock on a dat
Define the Wait for graph Ans: The wait-for-graph is a directed graph and consist of nodes and directed arcs; the nodes of the graph are active transactions. An arc of the grap
What is the use of unique function? UNIQUE function: If UNIQUE is specified then only unique values are used to computed the mean.
Saving Derived Attributes to Avoid Re-computation Data that is derived from other data should be stored in the computed form to avoid re-computation. For this, we could define
Limitations of File Based System The file-based system has some limitations. The limitations are listed as follows: Isolation and separation of data: When the data is
In an organisation various projects are undertaken. Each projects can employ one or more employees. Every employee can work on one or more projects. Each project is undertaken on
Three way to handle missing field val
When every condition appears with equality condition (=) only. c) Natural join (denoted by R*S) When two join attributes have the similar name in both relations. (Tha
Explain the concept of a data model ? Data Model - Model is an abstraction procedure which hides irrelevant details although highlighting details relevant to the application
Timestamps For Read operations: If TS (T) If TS (T) >= W-timestamp (Q), then the transaction T is trying to read a value of data item Q which has been written and committed
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