[jeletonskelly]

To say that Facebook uses PHP and MySQL is to leave out the truth, honestly. They are a part of the stack, yes, but they aren't what makes the application scale to billions of requests. It would be like saying the local coffee shops website using Wordpress with a MySQL backend is using the same tech as Facebook. It's laughable.

[wslh]

They choose MySQL vs a lot of other alternatives for some reason and this reasoning can be applied to your use case.

> They are a part of the stack, yes, but they aren't what makes the application scale to billions of requests.

These are not just part of the stack, these are critical components within the stack.

[threeseed]

To say that PHP/MySQL is just a "part of Facebook's stack" is laughable.

They are the core components of Facebook. Normal people understand that the characteristics of Facebook's architecture is unique to just Facebook. They can get away with sharding/colocating data that nobody else can. The rest of us have a tonne of integrated data that requires complex joins (whether at the application or database layer).

[spacemanmatt]

They are edge components of Facebook. Just from a brief interaction with FB recruiters, I learned they use a lot of Vertica in their back-office. Please don't propose that they are using MySQL for their main business when it's only powering app nodes which are just POPs fed by their real (internal) services. Approximately speaking.