Where can I get a large sample database for practising MySQL query optimization [closed]

Question

Can anyone give a reference to a substantially large sample database which I can import into MySQL to test and learn optimization and benchmarking?
The database should have at least 6-8 tables with lots of foreign keys in between them, i.e a complete database. The MySQL employees database looked promising, but the download page has 3 download links, clicking on any of which opens a page in a browser with a god-awful amount of binary data, dont know what to do with that.

Answer 1

StackOverflow itself publishes a database that could be used for this kind of testing. It's a fast download using BitTorrent since there's a lot of seeders.

Answer 2

there is large dataset on mysql website