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Why should database software carry out atomic transactions, which is one requirement of the ACID test, when OL

Database software should meet the requirements of what is known as the ACID test. Why should database software carry out atomic transactions, which is one requirement of the ACID test, when OLTP is used?

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A.
So that the rules for database integrity can be established

B.
So that the database performs transactions as a single unit without interruption

C.
To ensure that rollbacks cannot take place

D.
To prevent concurrent processes from interacting with each other

Explanation:
B: Online transaction processing (OLTP) is used when databases are clustered to provide high fault tolerance and performance. It provides mechanisms to watch for and deal with
problems when they occur. For example, if a process stops functioning, the monitor mechanisms within OLTP can detect this and attempt to restart the process. If the process cannot
be restarted, then the transaction taking place will be rolled back to ensure no data is corrupted or that only part of a transaction happens. OLTP records transactions as they occur (in
real time), which usually updates more than one database in a distributed environment. This type of complexity can introduce many integrity threats, so the database software should
implement the characteristics of what’s known as the ACID test:
Atomicity Divides transactions into units of work and ensures that all modifications take effect or none takes effect. Either the changes are committed or the database is rolled back.
Consistency A transaction must follow the integrity policy developed for that particular database and ensure all data are consistent in the different databases.
Isolation Transactions execute in isolation until completed, without interacting with other transactions. The results of the modification are not available until the transaction is completed.
Durability Once the transaction is verified as accurate on all systems, it is committed, and the databases cannot be rolled back.

The term “atomic” means that the units of a transaction will occur together or not at all, thereby ensuring that if one operation fails, the others will not be carried out and corrupt the data in the database.
A is incorrect because OLTP and ACID enforce, but do not establish, the integrity rules that are outlined in the database security policy. Representing the letter C in ACID,
consistency relates to the enforcement and enforceability of integrity rules. Database software that demonstrates consistency conducts transactions that follow a specific integrity policy
and ensure all data are the same in the different databases.
C is incorrect because atomicity divides transactions into units of work and ensures that all modifications take effect or none takes effect. Either the changes are committed or the
database is rolled back. This means if something does not happen correctly, the database is reverted (rolled back) to its original state. After the transaction happens properly, a
rollback cannot take place, which is the durability component of the ACID test. This question is specifically asking about the atomic transaction approach, not durability.
D is incorrect because atomic transactions do not address the isolation of processes that are carrying out database transactions; this is the “isolation” component of the ACID test. It
is important that a process that is carrying out a transaction cannot be interrupted or modified by another process. This is to ensure the integrity, accuracy, and confidentiality of the
data that is being processed during the transaction

One Comment on “Why should database software carry out atomic transactions, which is one requirement of the ACID test, when OL

  1. joe says:

    Online transaction processing (OLTP) is used when databases are clustered to provide high fault tolerance and performance. It provides mechanisms to watch for and deal with problems when they occur.

    Atomic transactions guarantee that any partial updates are rolled back automatically in the event of a failure.




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