A distributed transaction, Database Management System

A Distributed Transaction

Let us demonstrate the concept of a distributed transaction by considering a banking system having of three branches located in 3 different cities. Every branch has its own computer with a database having of all the accounts maintained at that branch. Each such installation is therefore a site. There also exists one single site which preserves information about all the other branches of the bank. Assume that the database systems at the several sites are based on the relational model. Every branch preserves its portion of the relation: DEPOSIT (DEPOSIT-BRANCH) where DEPOSIT-BRANCH = (branch-name, customer-name, account-number, balance)

A site having information about the 4 branches maintains the relation branch- details, which has the schema as:

BRANCH-DETAILS (Financial_ health, branch-name, city)

There are other relations maintained at the several sites which are ignored for the purpose of our example.

A local transaction is a transaction that accesses accounts in only one single site, at which the transaction was started. A global transaction, on the other hand, is one which either accesses accounts in a site dissimilar from the one at which the transaction was started, or accesses accounts in various different sites. To demonstrate the difference among these two types of transactions, take the transaction to add Rs.5000 to account number 177 located at the Delhi branch. If the transaction was started at the Delhi branch, then it is considered local; or else, it is considered global. A transaction to transfer Rs.5000 from account 177 to account 305, which is located at the Bombay branch, is a global transaction as accounts in two dissimilar sites are accessed as a result of its implementation. A transaction finding the total financial standing of each branch is global.

What creates the above configuration a distributed database system are the facts that:

  • The several sites may be locally controlled yet are aware of each other.
  • Every site gives an environment for executing both global and local transactions.

Though, a user need not know whether on underlying application is distributed or not.

Posted Date: 3/12/2013 5:51:33 AM | Location : United States

Related Discussions:- A distributed transaction, Assignment Help, Ask Question on A distributed transaction, Get Answer, Expert's Help, A distributed transaction Discussions

Write discussion on A distributed transaction
Your posts are moderated
Related Questions
A constraint named less_than_20 was defined on the field date_of_birth of table student. Delete this constraint. ALTER TABLE student DROP CONSTRAINT less_than_20;

can you please explain with the help of suitable example the difference between conflict equivalence and conflict serializability?

Differentiate between natural join and outer join? Natural join is a binary operator which is written as (R * S) where as R and S are relations. The output of the natural join

Dirty Reads: T10 reads a value which is updated by T9. This update has not been committed and T9 aborts. T9 T10 Value of x old value = 200

Write a query to define tables students and teachers as sub tables of people? Create table students of student under people Create table teachers of teacher under people

Use of partial data by applications : In common, applications work with views rather than whole relations. Thus, it may be more appropriate to work with subsets of relations rather

What is data block? Data Block - In oracle the data blocks are referred to as tablespaces. A tablespace is an fields of disk consisting of one or more disk files. A tablespace

What is Data Storage? The storage structures and access methods used by database system are specified by a set of explanation in a special type of DDL called data storage-defin

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Explain five duties of Database Administrator? 1. DBA administers the three stages of the database and, in consultation along with the whole user community, sets up an defin