Partioning a table with a big index, does it help?

[Andries Bruinsma]

I've got a really big table which looks like this:

respID (int)
questID (int)
answer (int)

No primary key.

I've created an index on all 3 fields, but it is getting so big that mysql has problems with loading the index into memory because of its size. Now I was trying some partitioning experiments, but I can't find out the best way to partition this table.

Will partitioning help solve my performance issues on this big table? And what is the best way to parition this one, on questID or a combination? Most of the times we use the questID and answer in our queries.

Any help is appreciated!

Rgs