Define granularity and hierarchy of granularity of locks, Database Management System

Assignment Help:

Define granularity, hierarchy of granularity of locks & multiple granularity locking. Explain the modified two phase locking along with multiple granularity locking.

Ans: The size of the data item selected as a unit of protection through a concurrency control protocol is granularity. 

When the granularity is denoted in a hierarchical structure in which each node denotes data items of different sizes we acquire the hierarchy of granularity. 

In multiple granularity locking there are three kinds of locks - shared, exclusive and intention lock.

 Modified two-phase locking strategy

1)  No lock can be granted once any node has been unlocked

2)  No node might be locked till its parent has an intention lock

3)  No node might be unlocked till all its descendants are unlocked.


Related Discussions:- Define granularity and hierarchy of granularity of locks

Explain briefly concurrent task by taking an example, Explain briefly concu...

Explain briefly concurrent task by taking an example. Concurrent Task- The concurrent occurrence of more than one event is called concurrent task. Operating systems can handl

Explain the ansi sparc architecture, Explain the ANSI SPARC architecture ...

Explain the ANSI SPARC architecture The three-schema architecture is as well known as ANSI SPARC architecture. The aim of the three-schema architecture is to separate the user

Which is another name for weak entity, Which is another name for weak entit...

Which is another name for weak entity? Child is another name of weak entity.

Create database for car application, The Database MySQL scripts cars_f...

The Database MySQL scripts cars_for_sale.sql and car_details.sql containing the data to use for this task have been supplied. To complete this task, you need to first create

What are the two types of errors, What are the two types of errors? The...

What are the two types of errors? The two types of errors are: a) Logical error b) System error

Draw and explain the three level architecture of database, Draw and explain...

Draw and explain the three level architecture of the database system? A DBMS gives three levels of data is said to follow three-level architecture. The trget of the three-schem

A step-wise distributed database design methodology, A step-wise distribute...

A step-wise distributed database design methodology Following is a step-wise methodology for distributed database design. (1) Examine the nature of distribution. Find out wh

Relational database, Consider the following relational database: STUDENT (n...

Consider the following relational database: STUDENT (name, student#, class, major) COURSE (course name, course#, credit hours, department) SECTION (section identifier, course#, sem

Define two-phase locking protocol, Define two-phase locking protocol. A...

Define two-phase locking protocol. Ans: Two-phase locking is significance in the context of ensuring that schedules are serializable. The two-phase locking protocol defines a p

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd