Explain the lock based protocol, Database Management System

Assignment Help:

Lock Based Protocol

A lock is nothing but a mechanism that tells the DBMS whether a particular data item is being used by any transaction for read/write purpose. As there are two types of operations, i.e. read and write, whose basic nature are dissimilar, the locks for read and write operation might be behave differently.

Read operation performed by dissimilar transactions on the same data item poses less of a challenge. The value of the data item, if constant, can be read by any number of transactions at any given time.

 


Related Discussions:- Explain the lock based protocol

ER DIAGRAM, draw ER diagram of student entity and course entity where attri...

draw ER diagram of student entity and course entity where attribute of student entity are student roll, student name, student phone and student address and attribute of course enti

Functional dependency, Functional Dependency Consider a relation R that...

Functional Dependency Consider a relation R that has 2 attributes A and B. The attribute B of the relation is functionally dependent on the attribute A if and only if for every

A b-tree of order how much children m has maximum, A B-tree of order how mu...

A B-tree of order how much children m has maximum ? m has maximum m mchildren in a B tree.

Write query to list the staff who work within the branch, Consider the foll...

Consider the following relations: BRANCH( bno, street, area, city, pcode, Tel_no, Fax_no) STAFF( Sno, Fname, Lname, address, position , salary, bno) Express the subsequent qu

Search the name department number and salary of employees , Example : Searc...

Example : Search the name, department number and salary of employees drawing minimum salary in that department. SELECT ENAME, SAL, DEPTNO  FROM EMP WHERE SAL IN (SELECT MI

Why do you go for sorting your query results, Why do you go for sorting you...

Why do you go for sorting your query results? SQL SELECT command to fetch data from MySQL table. Whenever you select rows, the MySQL server is free to return them in any order

Explain the exec statement in sql, Explain the EXEC statement in SQL  A...

Explain the EXEC statement in SQL  Ans: All statements which start with EXEC SQL are embedded SQL database statements. High level languages such as C can be employed to write a

Why like predicate used for, Why Like predicate used for? LIKE predicat...

Why Like predicate used for? LIKE predicate: The LIKE predicate searches for strings in which have a certain pattern.

Explain the structure of well formed formulae, Explain the structure of wel...

Explain the structure of well formed formulae in relational calculus. Ans: a. An atom is a formula b. If P1 is a formula, after that so are ¬P1 and (P1) c. If P1 and P2 a

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