i think that everything is mapped correctly. i even stripped everything down to be as simple as i could make it. it is still trying to add new records containing only the new derived 'dateYear' for some reason. this is not possible because i have an employeeID field that is the primary key with Allow NULLS unchecked so the package is bombing on that error. if i check Allow NULLS on employeeID in the table and run the package, then it creates the new records, with only 'dateYear' filled in.
source
SELECT
datestamp, dateYear
FROM
dbo.emDetail
Derived Column Name
dateYear
Derived Column
Replace 'dateYear'
Expression
DATEPART("yyyy",GETDATE())
destination
SELECT
datestamp, dateYear
FROM
dbo.emDetail