VietMX Staff asked 3 years ago
PACELC theorem give further detail on what happen when there is no partitioning (i.e., network is healthy). The acronym means if we suffer from network partitioning (P), we have to choose between availability (A) or consistency (C), else (E) we have to choose between latency (L) or consistency (C).
The whole thesis is assuming we maintain high availability by replication. So when there is failure, CAP theorem prevails. But if not, we still have to consider the tradeoff between consistency and latency of a replicated system. Now we can classify come database systems:
- MySQL cluster: PC+EC, such RDBMS always prioritize for consistency of data
- Amazon DynamoDB: PA+EL, it aimed for fast respond time by trading off consistency of data
