The AWS and MongoDB Infrastructure of Parse
"our idea is that developers should know about details such as schemas and indexes (the Parse engineers strongly agreed in hindsight)."Many engineers I have worked with like to throw around terms like: "CQRS", "Event sourcing", "no schema's", "document-based storage", "denormalize everything" and more. However, when pushed, I often see that they lack a basic understanding of DBMSes, and fill up this gap by basically running away from it. For 95% of the jobs, a simple, non-replicated (but backed-up) DBMS will do just fine. The remaining 3% might benefit from some sharding and the final 2% are for specialized databases, such as column-oriented DBMSes, document-oriented DBMSes or graph-based databases.At this very moment, I'm working on a classical DBMS, searching through around 200 million tuples within the order of 2 seconds (partially stored columnar using psql array types and GIN indexes). Not for a second did I consider using any kind of specialized database, nor optimized algorithms, except for some application-level caching. Some problems are caused by DBMS to backend and backend-to-frontend network utilization, which is generally not something a specialized DBMS can solve.