Does any one have an easy to understand link or other reading (I'm in marketing) on how to achieve performance and scalability when it is not possible to group requests to the database? (Not sure that I'm explaining this well but for my company each transaction must be handeled seperately from start to finish and I am not sure that it will be possible to reach targets of 500 transactions per second with quick processing times becuase we can't limit the number of times we go to the RDBMS.)

Any help would be really appreciated