RE: Length limit of 500 on primary keys?

[Chris Bolt]

> Is there a way to raise this limit? We have some tables with columns that
> are VARCHAR(200), and need to make a primary key based on combinations of
> these columns (in some cases, upto 4 columns), and MySQL complains for all
> of these table definitions that "Specified key was too long. Max key
> length is 500".

Why do you need to index the entire column? You can just index a prefix of
the column, like the first 125 bytes of each column.