Transaction Processing

A form of computing.

In computing terms a 'transaction' is moving a chunk of data from one place to another whilst making sure everything is within the system is still consistent. If the consistency check fails then the system can 'roll back' to its state before the transaction happened.

For example, imagine you are moving a record from one database table to another, usually this is fine as primary keys, secondary keys and dependent calculations all track the movement. But what if the power fails just as the movement was happening? It is quite possible that the data is now inconsistent with only part of the transaction having completed properly. In this case the system would be rolled back to bring it back in line, then try the transaction again.

Transaction processing is very important in financial systems where all the money moving around must balance.

2020-10