In the first part of this article we examined the types of conflicts and their causes. In this part, we will analyse some of the methods available to deal with conflicts.
Pessimistic locking (or: conflicts won't happen)
Applicability: synchronous clusters with 2pc
We've covered this topic in the previous article, but it's worth repeating. If you use a synchronous cluster, you don't have conflicts. For example, MySQL Cluster ensures consistent data with updates coming from different nodes. However, MySQL Cluster is not a replacement for a MySQL server, and it has severe limitations.
Applicability: synchronous clusters without 2pc (Galera)
Conflicting transactions proceed on different nodes with local locking. The last one then …[Read more]