Conflict operation

In computer science, two operations are called conflicting in connection with transaction systems if the order of their execution cannot be reversed without changing the result of the operations. It is also said that the operations are in conflict , do not commute or are incompatible and the operations are called conflict operations .

In the read-write model, two operations are conflicting if both access the same data element and at least one of the two is a write access.

Illustrative example

The following example should serve to clarify the term:

When putting on clothes, the following two operations appear:

1. Put on your panties.
2. Put on your pants.

These two operations are conflicting because if you reverse their order, the result is less than desirable. In the case of conflict operations, the order in which they must be carried out must always be specified.

Formal representation and organization of conflict operations

The notation corresponds to the crossed-out mathematical symbol for "commutated":

${\displaystyle o_{1}\not \|o_{2}}$

Partial orders are used to formally arrange conflict operations. This means that a meaningful sequence of conflicting operations can be obtained with the help of topological sorting .