Mysql hash partition
jkavalik is right.

I'll say it more strongly: PARTITION BY HASH is possibly useless in any situation for enhancing performance.

Your table is referenced only by the PRIMARY KEY(id), correct?  And it is InnoDB, correct?  If you have a million rows, the BTree that contains the PK and all the data is about 3 levels deep.  For a _trillion_rows, it will be about 6 levels.

The million-fold increase in data size (from 1M to 1T) might slow down a "point query" by a factor of 2.  That's all.