Select certain field based on another field in table - mysql

Question

I have three tables that I use which has proved this problem to be way out of my league.
The first is the hierachy table which looks like this
USER_ID, USER_LEVEL, Store_Manager_ID, Team_Manager_ID
------------------------------------------------------
1, 0, -, -
2, 1, 1, -
3, 2, 1, 2
4, 2, 1, 2
5, 2, 1, 2
This just shows the hierachy of the user. So user 1 has a level of 0 which means he is th store manager and so he has no store manager on top of him so his store manager id is nothing and team manager is obviously nothing.
The second user is the team manager and so level = 1 and store manager is 1(the first guy)
The third, forth and fifth are workers under 1 and 2 respectively.
The second is a login table which looks like this
USER_ID, EMAIL
--------------------------
1, john.smith#gmail.com
2, ron.jones#gmail.com
3, tom.graham#gmail.com
4, bill.small#gmail.com
The email is the login, no password.
The third is an alias table which looks like this
USER_ID, ALIAS_ID
--------------------
2, 5
The alias tables shows how user 5 is an alias of user 2. So he is the same person and has the same login. However he can be in two places in the hierachy at once i.e. a team manager and a worker at the same time.
My question is.
If I know that user 2 will be logging in as his alias, i.e. a worker before login.
When user 2 logs in, how can I select the id of the leader of the users account based on the level.
For example if I logged in as ron.jones#gmail.com (user 2) under my alias account.
The alias id of user 2 is 5 and based on the hierachy user 5 is level 2 i.e. a worker and so I should return the id of his team manager not his store manager.
So I would then return 2, i.e. himself (a little bizarre in the this case but besides the point)

Answer 1

This will give the answer you are looking for (if I understand the question correctly):
SELECT team_manager_id
FROM hierarchy h
INNER JOIN aliases a ON h.user_id = a.alias_id
INNER JOIN login l ON a.user_id = l.user_id
WHERE email = 'ron.jones#gmail.com';

Answer 2

Select user_ID, User_level, Store_Manager_ID, Team_Manager_ID
FROM Hierachy H
INNER JOIN Alias A on A.Alias_ID = H.User_Id
Where A.User_ID = 2
Assumes: that 1 a user doesn't have more than 1 alias, if it does you'll get multiple records back for the same user.
Assumes you don't carea bout the record 2 in hierachy as all you're after is 5.

Answer 3

If I understand correctly, you want the managers of a user, either based on the user or the alias for the user.
The following query does two joins, one to the user table and one to the alias table:
SELECT team_manager_id
FROM h.user_id = a.alias_id INNER JOIN
login l
ON a.user_id = l.user_id join
hierarchy huser
on huser.user_id = a.alias_id join
hierarchy halias
on halias.user_id = l.user_id
WHERE l.email = 'ron.jones#gmail.com' and
huser.team_manager_id is not null and
halias.team_manager_id is not null
It also checks that the manager is not null, returning only managers on the alias. This returns all such managers. Do you need a particular one, say from the lowest level of the hierarchy?