Ask HN: How do I prevent database bottlenecks on my web app?

I have done web apps before but only in the classroom so I've not dealt with real customers and heavy database loads. Now I am working on my first serious web app for my startup which provides each customer with their own unique subdomain.

I understand that I will have to learn on to go but I would like to avoid the dreaded database bottlenecks I hear about as much as possible. To this end, what guiding principles can I use to design the schema? Will the relational database model I learnt in school be able to scale well or will it make bottlenecks imminent?

Google for nginx, Cassandra, memcache, node.js, RabbitMQ, and visit highscalability.com. I'm sure folks will chime in with some other useful nouns and urls.

Highscalability.com has links to videos and articles of several major sites and their architecture.

The youtube video was quite informative.

On to the schema...without knowing your specifics, I would say to map your entities in a normalized form, but, you will most likely bust most of them out and denormalize as influenced by your display page (view) or particular portions of it.

Also play around with Amazon AWS. You can play around for several dollars an hour without having to invest in your own hardware.

Also, lurk around stackoverflow.com

Defining the right indexes is the key until you outgrow the RAM in the server. You can be crawling with one schema, define a few indexes, and suddenly be able to handle a hundred times more activity. What indexes are right depends on what queries you need to execute, not just what data's in the tables, so read up on how indexes are used by your RDBMS, not just how they're defined.

Normalize until it hurts, denormalize until it works.

Build your database tier using everything they taught you in the classroom. Normalization is your friend here. Why? When you've effectively normalized your database, you can monitor the results of queries and eventually introduce the optimizations that you need to make things run faster.

The problems that sites like highscalability.com deal with are far beyond the scale of most endeavors. If you run into massive scale problems, be very happy because it means you're building something that people want and you can afford to throw some money at the problem ;)

I know people who have production databases with 30+ terabytes that is sitting in a relational database. If you design well, you shouldn't have any problems reaching those goals.