Just what is 'A big database'?

Question

Ok, dumb question I know but I see the nebulous comment \'a large database\' as well as small and medium and I wonder just what that means. Can someone define what a small, medi

Answer 1

Large database are ones that force you have to stop using relational databases.

In other words, a normalized, relational database where all the indexes in the world can't help you meet your response time requirements because of the massive JOINs.

If you've ever had to abandon relational databases for something else, you're either a poor database developer, have no expert DBA, or have a very large database.