Conflictserialiseerbaar

Conflictserialiseerbaar is a term used in the field of database systems, specifically in the context of transaction isolation levels. It refers to a level of isolation that ensures transactions appear to be executed serially, even though they may be interleaved in reality. This isolation level is less strict than serializability, which requires that the outcome of a set of transactions is equivalent to some serial execution of those transactions.

In a conflictserialiseerbaar isolation level, transactions are allowed to read data that has been written by other transactions, but only if those writes do not conflict with the reads of the current transaction. A conflict occurs when a transaction reads data that has been written by another transaction, or when a transaction writes data that has been read by another transaction. By ensuring that such conflicts are resolved in a way that maintains the illusion of serial execution, conflictserialiseerbaar provides a balance between performance and consistency.

This isolation level is often used in systems where a high degree of concurrency is required, but where the risk of anomalies such as dirty reads, non-repeatable reads, and phantom reads is acceptable. It is implemented by using a concurrency control mechanism, such as two-phase locking or timestamp ordering, to manage the order in which transactions access data.

Conflictserialiseerbaar is a useful concept in the design and implementation of database systems, as it allows developers to make trade-offs between performance and consistency based on the specific requirements of their applications. By understanding the properties and implications of conflictserialiseerbaar, database designers can create systems that are both efficient and reliable.