Ratan

• Mar 25th, 2005

 

One or more SQL statements that mark the completion of a task is called a transaction.

Gayathri

• Aug 22nd, 2005

 

A collection of DML statements that form a 
logical unit of work is called a transaction

jagdish

• Aug 22nd, 2005

 

It is a operation on database / table. which has to be confirmed after completion.  
It may be single sql stm or multiple stm 

vipin

• Aug 28th, 2005

 

vipco1974@yahoo.com 
 
whatever you do before executing a commit or rollback is called as a transaction.

kishorebabu K M

• Sep 20th, 2005

 

Transaction is a set of DML statements end up once a commit or rollback statements are encountered

annathurai

• Oct 15th, 2005

 

transaction nothing but logical group of unit is called the transaction

Srikanta Mallik

• Feb 20th, 2006

 

   Hi,

     Transaction is a logical unit of dadabase processing,acollection of logical process.

    By

  Srikanta Mallik

Haldia Institute Of Technology.

Haldia

Suraj Marathe

• May 5th, 2006

 

Transaction should follow ACID property.

A => Atomicity

C => Consistancy

I =>integrity

D =>durability

agupta_22

 Profile Answers by agupta_22 

• May 13th, 2006

 

Transaction should commit as whole or should rollback as whole.
A transaction should possess following properties

1) Atomicity refers to the ability of the DBMS to guarantee that either all of the tasks of a transaction are performed or none of them are. The transfer of funds can be completed or it can fail for a multitude of reasons, but atomicity guarantees that one account won't be debited if the other is not credited as well.
2) Consistency refers to the database being in a legal state when the transaction begins and when it ends. This means that a transaction can't break the rules, or integrity constraints, of the database. If an integrity constraint states that all accounts must have a positive balance, then any transaction violating this rule will be aborted.
3) Isolation refers to the ability of the application to make operations in a transaction appear isolated from all other operations. This means that no operation outside the transaction can ever see the data in an intermediate state; a bank manager can see the transferred funds on one account or the other, but never on both?even if she ran her query while the transfer was still being processed. More formally, isolation means the transaction history (or schedule) is serializable. For performance reasons, this ability is the most often relaxed constraint. See the isolation article for more details.
4) Durability refers to the guarantee that once the user has been notified of success, the transaction will persist, and not be undone. This means it will survive system failure, and that the database system has checked the integrity constraints and won't need to abort the transaction. Typically, all transactions are written into a log that can be played back to recreate the system to its state right before the failure. A transaction can only be deemed committed after it is safely in the log.

thumatinagaraju

 Profile Answers by thumatinagaraju Questions by thumatinagaraju

• Oct 24th, 2006

 

nice reply friend vipin

kshsingh1

 Profile Answers by kshsingh1 

• Jan 22nd, 2007

 

A transaction is a logical unit of work that contains one or more SQL statements.

Suraen

 Profile Answers by Suraen 

• Mar 3rd, 2009

 

Transaction encapsulates SQL commands and work as a single unit.
All the SQL statements defined in the transaction should work successfully.
Every transaction follow transaction properties ACID i.e., Atomicity,
Consistency, Isolation, Durability to qualify as valid transaction.

geeksterrahul

 Profile Answers by geeksterrahul 

• Aug 7th, 2009

 

A transaction is a UNIT of work. It contains a set of tasks to be completed as a SINGULAR UNIT of work.

bandna chaudhary

 Profile Answers by bandna chaudhary 

• Dec 8th, 2009

 

Transaction is a logical unit of work area.

csbhaskar

 Profile Answers by csbhaskar 

• Mar 25th, 2011

 

A transaction is a logical unit of database related work that contains one or more valid and executable SQL statements.

A transaction begins with the first executable SQL statement and ends when it is committed or rolled back. However, commit or roll back may either be called explicitly by command execution or implicitly by some database activity.