Updating tables based on Dates

Question

In my application I use some tables with a date field.
table: employee
period date (e.g. 01-01-2004, 01-02-204, 01-03-2004)
target money
result money
table: project
date date (e.g. 15-01-2004, 20-01-2004, 03-02-2004)
revenue money
If I book a new project the table employee should be updated with result = result + revenue. If there is a new project on 15-01-2004 the record in employee where period = 01-01-2004 should be updated.
Can someone help me with a sample code for this problem?

Answer 1

Assuming you have a block in the form call PROJ with fields DATE, REVENUE and EMP_NO. Also that a record exists for the employee and period date.
Create PRE-INSERT and PRE-UPDATE triggers on the block PROJ containing
begin
update employee
set result=result+:PROJ.REVENUE
where period_date=trunc(:PROJ.DATE,'Mon')
and emp_no=:PROJ.EMP_NO;
end