Correct me if I'm misunderstanding. Refer to the following sentence:Stack Overflow copied a key part of the Wikipedia database design.  This turned out to be a mistake which will need massive and painful  database refactoring to fix. The refactorings will be to avoid  excessive joins in a lot of key queries. This is the key lesson from  giant multi-terabyte table schemas (like Googles BigTable) which are  completely join-free. This is significant because Stack Overflow's  database is almost completely in RAM and the joins still exact too  high a cost.1Actually I'm trying to pass from the interest on single technology like Asp.net MVC to architectures design.Can you better clarify the quoted sentence?[1] http://highscalability.com/stack-overflow-architecture
Why are JOINS deprecated for a in-memory database?
architecture;database;enterprise architecture;scalability
You've misread the directionality of the quote. JOINs are generally discouraged for high-volume systems, because they are expensive (because of I/O being necessary more than one table). SO put their database into RAM specifically to avoid being hit by double disk I/O costs, and it turns out that even without physical I/O, the double table searching is still too slow. That shows you just how inefficient JOINs are on large volumes of data.