I think your performance here stems more from configuration than from MySQL vs Redis. If you're using Redis in-memory, if you dedicate the same amount of memor

I think your performance here stems more from configuration than from MySQL vs Redis. If you're using Redis in-memory, if you dedicate the same amount of memory to your database, you should get roughly comparable performance between MySQL/PostreSQL and Redis. The under-the-hood differences if you're in memory just aren't that great, particularly because modern machines have such ridiculously powerful CPUs. Yes, it sounds like you'll have to do table join(s); yes, the joined tables need indexes; yes, you have the SQL parsing overhead; yes, it's a B-tree rather than hash-based indexing. But I'd be very surprised if you ended up with the order-of-magnitude differences you're suggesting. One of the things we're working on with FathomDB is ways to identify slow queries and help figure out what to do about them. If you're game, you can contact me with the queries and the table structure you were using in SQL and I'll try to figure out what's going on!