Explain two phase locking protocol, Database Management System

Assignment Help:

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 transaction. Such type of transaction can be divided into two phases: and expanding or growing (first) phase, throughout which new locks on items can be acquired but none can be released; and a shrinking (second) phase, throughout which existing locks can be released but no new locks can be obtained. This two-phase protocol can make sure the serializability because all the data items needed by a transaction will be locked at the starting of the  transaction and if other transaction needs to use those data items then it has to wait till they become unlocked.


Related Discussions:- Explain two phase locking protocol

What is the role of order by clause, What is the role of ORDER By Clause? ...

What is the role of ORDER By Clause? ORDER BY clause: The ORDER BY clause permits you to sort the records in your result set. The ORDER BY clause can just be used in select s

What is known as a search key, What is known as a search key? An attrib...

What is known as a search key? An attribute or set of attributes used to look up records in a file is known as a search key.

Explain relevance of data dictionary in a database system, Explain the rele...

Explain the relevance of Data Dictionary in a Database System? Data dictionary is a database in its own right residing on the disk that consist of Meta data which is = Data abo

Multiple column queries-syntax, Multiple column Queries: Syntax: ...

Multiple column Queries: Syntax: SELECT COLUMN1, COL2,...... FROM TABLE WHERE (COLUMN1, COL2, ...) IN (SELECT COLUMN1, COL2,....  FROM TABLE WHERE );

Enforce referential integrity, Use Access 2007 to create a database calle...

Use Access 2007 to create a database called UniLib.mdb. - this file should be created on your personal drive at the university (or C: if you're using Access 2007 at home) and t

Define the terms key attribute and value set, Define the terms i) Key attr...

Define the terms i) Key attribute ii) Value set Key attribute: An entity type usually has an attribute whose values are exact from each individual entity in the collection. Su

Define atomicity and aggregation, Atomicity : Either all functions are lai...

Atomicity : Either all functions are laid out or none are. Users could not have to think about the effect of incomplete operations. DBMS ensures this by undoing the functions

Mention the various user privileges, Mention the various user privileges ...

Mention the various user privileges All privileges directly granted to the user or role. All privileges granted to roles that have been granted to the user or role.

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