Keeping information after a person leaves

Question

I have a PERSON table which is our list of people in the college. It's my main list and all other databases relate to it's ID column.
I am creating a list of grants and want to relate it to the PEOPLE table and have done so (see two table descriptions below). Now, when I need the first and last name of the person with the grant, I just include the PEOPLE table in the query and have the information.
SELECT
g.g_c_id,g.start_date,g.end_date,g.title,
p.id,p.fname,p.lname
FROM grants_contracts g, people p
WHERE g.id = p.id
The problem is that when people leave the college, we delete them from the PEOPLE table. While I don't have it cascade the delete to the GRANTS_CONTRACTS table so the information will still stay after they leave, I no longer will properly receive the first and last name and other info in the PEOPLE table. In fact, I bet I receive 0 records returned since the person no longer is in there.
So, to cure this, should I populate the GRANTS_CONTRACTS table with the information that I know that I'll need long term? I suppose we never know what we'll need long term. Or should I just make the person in the PEOPLE table 'inactive', keeping their information forever and always.
Or is there another solution?
create table PEOPLE (
id NUMBER Primary Key,
type VARCHAR2(50),
fname VARCHAR2(100),
lname VARCHAR2(100),
title VARCHAR2(100),
dept VARCHAR2(50),
create table GRANTS_CONTRACTS (
     g_c_id NUMBER Primary Key,
     id NUMBER REFERENCES people(id),
date_added date,
     start_date date,
     end_date date,
title VARCHAR2(300),
funding_agency VARCHAR2(300),
     funding NUMBER,
     abstract VARCHAR2(3000),
     related_file VARCHAR2(100),
     status VARCHAR2(50)
thanks all.
daniel

Answer 1

I would just keep the person table intact, and add a status column to show that they are inactive, terminated or whatever. There are several disadvantages with duplicating the data into the grants table. What happens when someone changes their last name? What if you later decide you need another column from person but have not replicated it?
John