Find 'missing' rows across two result sets - sql-server

Question

I've been struggling with this for days so apologies if I've over-confused things...
I have a series of tables that define:
Groups of skills
Skills
Skills within the above groups (many-to-many)
Job roles
The skills with those job roles (many-to-many)
The structure of the database looks like this:
I need to create a result set that displays the following data:
For all of the job roles, show all of the skills within those job
roles. However, also include skills within the respective groups that
were not included in each role (indicated with NULL or by any
other method).
Please see this working code to create the tables and data. SQL Fiddle
Apologies for the length, I did lots of inserts to create a realistic example.
Notice that the PowerPoint skill is not added to the HR Manager role, but other skills from that same group are added. Also notice that the Recruitment Policy skill is not added to the Software Manager role, but I do not need to see this gap because no other skills in that group exist in the role.
The results I would aim for would resemble this (excludes Super Star role for brevity):
RoleTitle GroupTitle SkillTitle SkillIsInRole
----------------------- -------------------------- --------------------------------------
Software Manager Microsoft Office Excel 1
Software Manager Microsoft Office Word 1
Software Manager Microsoft Office PowerPoint 1
Software Manager Microsoft SQL Server Query Design 1
Software Manager Microsoft SQL Server Stored Procedures 1
Software Manager Microsoft SQL Server Failover Clustering 1
HR Manager Microsoft Office Excel 1
HR Manager Microsoft Office Word 1
HR Manager Microsoft Office PowerPoint NULL <-- not added to role but exists in same group as other used skills
HR Manager HR Recruitment Policy 1

Answer 1

Getting all skills for a group related to a role is somewhat simple and is handled in the relatively self explanatory roles cte below. From this the only way I can think of obtaining whether the skill was related 'directly' to the role is by OUTER APPLYING the result set to the result set of actual skills for role.
;WITH skills AS
(
SELECT g.GroupId, g.GroupTitle, s.SkillId, s.SkillTitle
FROM #tbl_GroupsSkills gs
INNER JOIN #tbl_Groups g ON g.GroupId = gs.GroupId
INNER JOIN #tbl_Skills s ON s.SkillId = gs.SkillId
)
, roles AS
(
SELECT DISTINCT jr.Id RoleId, jr.RoleTitle, gs.GroupId
FROM #tbl_jobroles jr
INNER JOIN #tbl_rolesskills rs ON rs.RoleId = jr.ID
INNER JOIN #tbl_GroupsSkills gs ON gs.LinkId = rs.LinkId
)
SELECT
roles.RoleTitle,
skills.GroupTitle,
skills.SkillTitle,
t.SkillIsInRole
FROM skills
JOIN roles ON roles.GroupId = skills.GroupId
OUTER APPLY
(
SELECT 1 SkillIsInRole
FROM #tbl_rolesskills rs
INNER JOIN #tbl_jobroles r ON rs.RoleID = r.ID
INNER JOIN #tbl_groupsskills gs ON gs.LinkID = rs.LinkID
INNER JOIN #tbl_groups g ON g.groupID = gs.GroupID
INNER JOIN #tbl_skills s ON s.skillID = gs.SkillID
WHERE s.SkillId = skills.SkillId
AND g.GroupId = skills.GroupId
AND r.Id = roles.RoleId
) t
ORDER BY roles.RoleTitle, skills.GroupTitle, skills.SkillTitle
Edit: the OUTER APPLY could be handled with a LEFT JOIN
LEFT JOIN (
SELECT s.SkillId, g.GroupId, r.Id RoleId, 1 SkillIsInRole
FROM #tbl_rolesskills rs
INNER JOIN #tbl_jobroles r ON rs.RoleID = r.ID
INNER JOIN #tbl_groupsskills gs ON gs.LinkID = rs.LinkID
INNER JOIN #tbl_groups g ON g.groupID = gs.GroupID
INNER JOIN #tbl_skills s ON s.skillID = gs.SkillID
) t ON t.SkillId = skills.SkillId
AND t.GroupId = skills.GroupId
AND t.RoleId = roles.RoleId
demo

Answer 2

I think you have to prepare a set of all possible combinations Roles from one side and Group-skills from the other. This is done by making Decart multiplication (usually done by CROSS JOIN). As a result you will have a list of each role combined with a list of all possible Group-skills combinations. After that you can LEFT JOIN this result with table tbl_RolesSkills. This will give what you need. You can do this by using CTE or sub query.
Have to looks like this example
Actually CROSS JOIN is not needed, I missed part with "specific roles have only a specific group sets". Only one sub-query, can be done also with CTE (Common table expression).
I also exclude "Super Star" role. If you want to add it just remove WHERE section.