construct table for fast insert/select

[graceinfinity]

Hi,

I have tables with only 2 fields, key (char(30)) and value(blob), the blob in average is about 2K.

The table is going to store more than 20 million entries. I will keep inserting, selecting and deleting the table. I wonder what will the best way be to construct the table, i.e., how should I do 'create table ....'.

I know I need to index the key, but shall I also index the value? shall I set up key or primary key for the key? What is the way to construct table to achieve the best performance based on the fact that it's a SIMPLE (only 2 fileds) but GIANT table?

Thanks very much.