When are two schedules said to be view equivalent, Database Management System

Assignment Help:

When are two schedules said to be view equivalent?    

Ans: Two schedules that is denoted as S and S' are said to be view equivalent if the subsequent three conditions are met

1)  For every data item Q, if a transaction Ti reads the initial value of Q in schedule S, after that transaction Ti should in schedule S'  also read the initial value of Q.

2)  For every data item Q, if a transaction Ti executes read(Q)  in schedule S and that value was generated by Tj (if any) , then transaction Ti must in schedule S'  as well read the value of Q generated by Tj.

3)  For every data item Q, if a transaction if any that carries out the final write(Q) in schedule S should perform the final write(Q) in schedule S'.


Related Discussions:- When are two schedules said to be view equivalent

Database life cycle, Enumerate or state the steps in creating a relevant da...

Enumerate or state the steps in creating a relevant database of a shop.

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

Sql, example of embedded SQL query

example of embedded SQL query

Draw entity relationship diagram, Draw entity relationship diagram for the ...

Draw entity relationship diagram for the following scenario. A university has many departments whereas each department belongs to that particular uni. That uni has also many bui

Cluster analysis project, (a) Data Mining Process : In the context of t...

(a) Data Mining Process : In the context of this cluster analysis project , and in your own words , explain how you would execute the first stage of data mining, namely the "P

Dbms, You are managing the following database system: • DBMS: Oracle 11g ...

You are managing the following database system: • DBMS: Oracle 11g • OS: Sun Solaris • System architecture: Web-based application using ASP.Net • Purpose of Server: HR managem

Tuples-attributes , Consider a relation s over the attributes A and B wit...

Consider a relation s over the attributes A and B with the following characteristics: 5,000 tuples with 10 tuples per page A 2-level B+ tree index on attribute

User error-database errors, User error :  This contains errors in the progr...

User error :  This contains errors in the program (e.g., Logical errors) with errors made by online users of database.  These types of errors can be avoided by applying some check

Define shadow paging, Define shadow paging. An alternative to log-based...

Define shadow paging. An alternative to log-based crash recovery method is shadow paging. This technique requires fewer disk accesses than do the log-based methods.

DBMS, You are managing the following database system: • DBMS: Oracle 11g...

You are managing the following database system: • DBMS: Oracle 11g • OS: Sun Solaris • System architecture: Web-based application using ASP.Net • Purpose of Server: HR manage

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