I am developing an application that tracks work done.

The Work Items are the headers, and the History table contains the
line items. Standard one-to-many.

The user may set up a Work Item, then do work 3 different times, each
time becoming a record in the History table.

What I want to do is somehow keep the history records separated so
each each 'session' can be invoiced and reported on individually,
and still be able to view them all together, like in a memo field.

If I used a memo on a single history record, how would I go back and
retrieve specific information per date for editing or reporting
(without writing some huge parsing routine).

If I use individual records, how do I put it all together so that all
the history sessions for that work item look like one log as a whole.

Any help would be really appreciated

TIA