What database is best suited, especially in terms of disk usage, to millions of very small rows with a high insert, query, and delete volume?

I'm looking at a table struct开发者_如何学JAVAure that might look about like this:

| char(32) | char(32) | (boolean) |

The combination of the first two columns will be indexed. This database could easily have millions if not tens of millions of rows being inserted, queried, updated, and deleted every day. What's the best database tool for this? Is it MySQL or is there something more efficient that will use less space on disk?

Only that one table? Is the table shared, or only updated by one process?

If that's the only data you're keeping and it's maintained by a single process then any kind of database is probably overkill. Why not a linked list in memory?

Any relational database should be able to handle the load you describe assuming a proper logical and physical schema.

Does it have to be on a disk? Why not use memcached or redis? I assume you can make your "table" into "key/value" pairs?