Explain dynamic two-phase locking, Database Management System

Assignment Help:

Explain Dynamic Two-Phase Locking

Here a transaction locks a data item instantly earlier than any operation is applied on the data item.  After finishing all the operations on all the data items, it releases all the locks. An instance of dynamic 2PL is as following 

X(X)

Read (X)

X=X+M

Write (X)

X (Y)

Read (Y)

Y=Y+N

Write Y

Unlock (Y)

Unlock (X)


Related Discussions:- Explain dynamic two-phase locking

State about the activity diagram, State about the Activity Diagram Act...

State about the Activity Diagram Activity diagrams show flow from one activity to other. It is an ongoing non atomic execution within a state machine. Activity finally results

What is dml query langauge, What is DML Query Langauge? Data Manipulati...

What is DML Query Langauge? Data Manipulation Language (DML) - A data manipulation language is a language in which enables users to access or manipulate data as organized throu

ER diagram, Explain the conventions (relationships) for displaying an ER sc...

Explain the conventions (relationships) for displaying an ER schema as an ER diagram.

Example-revoke all on emp from mca12, Example:  //REVOKE ALL ON EMP FROM MC...

Example:  //REVOKE ALL ON EMP FROM MCA12;                              (All permissions will be cancelled) You can also cancel only some of the permissions. Drop: A user-

Explain nonclustered indexes, What is the difference between SQL Server 200...

What is the difference between SQL Server 2000 clustered and nonclustered indexes? With a clustered index, the data are kept in the bottom level of the index and in the similar

Define 3nf normal form, 3NF Normal Form A relation schema R is in 3NF ...

3NF Normal Form A relation schema R is in 3NF if it is in 2NF and for each FD X A either of the following is true X is a Super-key of R. A is a prime attribute of R

Database ass1, #quCreate a database design specification (Enhanced Entity R...

#quCreate a database design specification (Enhanced Entity Relationship Diagram (EERD) and Relational Data Model (RDM)) from the given business description. The RDM must be in 3rd

Datawarehouse, 1) Define a job scheduling strategy that will meet business ...

1) Define a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pict

Union - basic set operation, UNION If R1 and R2 are two union compatibl...

UNION If R1 and R2 are two union compatible relations then R3 = R1 ∪ R2 is the relation having tuples that are either in R1 or in R2 or in both. In case, R3 will have tuples

Explain about data independence, Data Independence This brings us to ou...

Data Independence This brings us to our next topic: data independence. It is the property of the database which tries to make sure that if we make any change in any level of sc

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