Create filter for most recent date using combined columns - sql

Question

I have created a filtering application in Access that references four simple tables:
Employee: Emp_ID, FirstName, LastName
Skill: Skill_ID, SkillName, SkillDescription, SkillGroup
Employee_Skill: Entry_ID, Emp_ID, Skill_ID, LevelofExperience, Dateupdated
SkillGroupName:SkillGroup_ID SkillGroupName`
Basically the idea of this database is to track employee skills and how the level of experience improves (or not!) over time. The problem I am facing is that I want the application to filter by the most recently updated combination of Skill and Employee. I have found the query that will allow for me to use the two columns as a distinct entity:
SELECT DISTINCT Emp_ID, Skill_ID FROM Employee_Skill
WHERE (SELECT MAX(DateUpdated)From Employee_Skill);
And it works perfectly on its own, but I don't know how to incorporate it either into my main query, which simply joins together the necessary columns for an easier end user experience. It does not visibly show Emp_ID or Skill_ID. It also doesn't in the VBA for the application. (-1 = Include all History; 0 = Only include most updated.)
Update:
I have been able to select the distinct combination of Employee and Skill through my main query by doing this:
SELECT
Employee.FirstName,
Employee.LastName,
Max(Employee_Skill.LevelOfExperience) AS LevelOfExperience,
Skill.SkillName,
Max(Employee_Skill.DateUpdated) AS DateUpdated,
Max(SkillGroup.SkillGroupName) AS SkillGroupName
FROM
SkillGroup INNER JOIN
(Skill INNER JOIN
(Employee INNER JOIN
Employee_Skill ON
Employee.Emp_ID = Employee_Skill.Emp_ID) ON
Skill.Skill_ID = Employee_Skill.Skill_ID) ON
SkillGroup.SkillGroup_ID = Skill.SkillGroup
WHERE
Employee.Active=True
GROUP BY
Employee.FirstName,
Employee.LastName,
Skill.SkillName
ORDER BY
Max(Employee_Skill.LevelOfExperience) DESC;
However, my forms and reports built on this query are stuck with only the option of seeing the most updated version. I am really hoping to have a dynamic form that removes the constraints as desired.

Answer 1

Not sure what you're doing with Max(Employee_Skill.LevelOfExperience) or Max(SkillGroup.SkillGroupName) but I think you need to stick with querying for the detail rows and then include another column marking the Max(Employee_Skill.DateUpdated) filter, like:
SELECT
Employee.FirstName,
Employee.LastName,
Employee_Skill.LevelOfExperience,
Skill.SkillName,
Employee_Skill.DateUpdated,
SkillGroup.SkillGroupName,
iif(max_dateUpdated=dateupdated,1,0) as is_max_DateUpdated
FROM
SkillGroup INNER JOIN
(Skill INNER JOIN
(Employee INNER JOIN
Employee_Skill ON
Employee.Emp_ID = Employee_Skill.Emp_ID) ON
Skill.Skill_ID = Employee_Skill.Skill_ID) ON
SkillGroup.SkillGroup_ID = Skill.SkillGroup inner join
(select
empID,
max(dateupdated) as max_dateUpdated
from
Employee_Skill
group by
empID) mx on
Employee.empID = mx.empID
WHERE
Employee.Active=True