One question that I have, after reading your post is when you mention "how to
handle the different dates of employment and different assignments for each
employee".

Here's my question. Does your system *need* to link the dates of a project
with the dates of an employees start/end date? In other words, let's say for
examples sake, that you have an employee that started working for your
company on Feb 1, 2008. He was assigned to a project that happened to have
started on Jan 1, 2008. You didn't mentioned tasks, but another person did,
so there's another factor.

What if you have one employee that starts a task/project and isn't able to
complete it for whatever reason (fired, quits, it doesn't matter why) and you
have to hire someone new.

This is why I ask the question, does your system need to keep track of
employees start/end dates, and !directly link! them to other dates (projects
or tasks) in the system?

Usually project tracking systems are really going to care. But if this
system is going to be used by the "bean counters" (accountants and/or
executive level - VP, etc) then it probably will matter, a lot!

"RAK" wrote:

I am trying to create an operational database. We hire temporary staff
through several different employment agencies to complete work on projects
for various clients. The term of employment is linked to individual projects
which are time limited and include different assignments within each project.
Many of the people we use have worked on many different projects at many
different times including several years. I started out thinking I needed 5
different tables and needed to use a many-many relationship. Here are the 5
tables I identified with some types of data:
Employee_Personal (usual type data)
Employment_History (includes Dates hired, Projects assigned at different
times, employment title per project, performance records; rehire status)
Agency (related to each employee, # provided for each project; performance
of employees provided)
Project (Clients, Dates, subjects, teams needed, staff needed)
Accounting [(Hours to complete project-administration pre training,
training, execution and administrative client reporting); (staff cost factors
computed for number of hours *title pay); (computer cost and needs per
project); space cost and needs per project)]

I started looking at the tables to try to see what relationships I needed
and if I needed junction tables. I didn’t know how to handle the different
dates of employment and different assignments for each employee and wondered
if I could use multi-valued fields or value lists for this data. Then I
started doubting if I was going in the right direction and thought I’d see if
I could get any help.