Hi All,
I am about to make some changes to a process we have. The new process
will have a new table who's job it is to store temporarily data such
as customer, clerkno,productno, storeno , amount, time.

On a new request from a front-end i will select against the primary
keys to ensure no other request for the same data has been made. This
is then sent to a backend system asynchronously if there is no match.
I will otherwise send a reject msg back to the store if i have the
same data in the table.

On the reply from the backend, i delete this record.
Now this table will hardly ever be filled as messages will be stored
and deleted within a second.

My question is, should i create this table with a single primary key
such as a sequence number or should it be a composite key of say
(customer, clerkno,productno, storeno).
I ask because, i am reluctant to have composite if the database is
maintaining indexes against each primary key column. I.e. four indexes
will have be be maintained for each insert or delete.

Should i just go with a single column sequence pk and then i just
index my customer column for a more restrictive select statement. Any
suggestions?

Thanks,