Software Architect's Handbook

Write-behind pattern

The write-behind pattern is sometimes used instead of the write-through pattern. They both treat the cache as the system-of-record but the timing of the write to the system-of-record is slightly different. Unlike the write-through pattern, in which the thread waits for the write to the database to complete, the write-behind pattern queues the writing of the data to the system-of-record. The advantage of this approach is that the thread can move on quicker, but it does mean that there is a short time when the data between the cache and the system-of-record will be inconsistent.