Is it worth to partition a MySQL table on a key, if this key is already an index?

I have a big MySQL table (around 50 GB, tens of millions of records), with one index key (a foreign key) that has around 2000 possible d开发者_开发百科ifferent values, and another index key (a VARCHAR(2)) that has 3 possible values.

Can I expect a significant performance increase if I partition the table based on either (or both) indices?

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You can't partition on a column that is not an index (or part of it), so yeah... it is worth it.

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Have you thought of de-normalising the table when there is three possible values if you have performance problems?