Question

I have 2 tables:

1. Team
id  group_head  initial_team
id : for id table (auto increment)
Group Head : employee id to add group head
initial team : initial team for this team


2. Team Sub
id  team_id     employee_id     parent  parent_id
id : id for table (auto increment)
team_id : id of the Team_table
employee_id : employee id
parent : value 0 if they child from team_sub, value 1 if they child from team
parent_id : if parent value 1 the parent id is id team, if parent value 0 the parent is id team sub

My question :
how to know total childs from team (group head)? Or how to know the bottom child from id team? If I delete id team the child is deleted too..

example :

id team : 1

data from team_ sub :
status parent: 1 parent_id : 1 (id this data is 1)
status parent: 0 parent_id : 1 (id this data is 2)
status parent: 0 parent_id : 2 (id this data is 3)
status parent: 0 parent_id : 3 (id this data is 4)
status parent: 0 parent_id : 4 (id this data is 5) 

id team : 2

data from team_ sub :
status parent: 1 parent_id : 2 (id this data is 6)
status parent: 0 parent_id : 6 (id this data is 7)
status parent: 0 parent_id : 7 (id this data is 8)
status parent: 0 parent_id : 8 (id this data is 9)
status parent: 0 parent_id : 9 (id this data is 10) 

where parent status is 1 , parent_id is id team..
where parent status is 0, parent_id is id team_sub..

this is relation data on image


sorry if my english is bad…

id team_sub 10 is child from id team 2 and id team_sub 5 is child from id team 1..

Answer 1

can’t check it right now, but should be like this if I understood you right :

SELECT * FROM Team_Sub WHERE (parent_id = 0)

It selects every entry that is technicaly part of the parent_id =1 aka part of the sub_team

If you just want a number of entrys that have this condition :

SELECT COUNT(*) FROM Team_Sub WHERE (parent_id = 0)

exaples:

//Count all entries in Team_ID 1:

SELECT COUNT(*) FROM Team_Sub WHERE (parent_id = 1) 


//Select all entrys in Team_ID 2:


SELECT * FROM Team_Sub WHERE (parent_id = 2) 


//Count all Entries that do belong to an Team_ID:

SELECT COUNT(*) FROM Team_Sub WHERE NOT (parent_id = 0) 


//Select all Entries that do belong to an Team_ID:

SELECT * FROM Team_Sub WHERE NOT (parent_id = 0)

I would recommend following structure:

status parent: 1 parent_id : 2 (id this data is 6)
status parent: 0 parent_id : 2 (id this data is 7)
status parent: 0 parent_id : 2 (id this data is 8)
status parent: 0 parent_id : 2 (id this data is 9)
status parent: 0 parent_id : 2 (id this data is 10) 

In this way you can detemine the Team by “parent_id” and the head of the team by “parent”.

so in example like above:

id 6 is Head of Team 2
id 7 is Subordinate of Team 2
id 8 is Subordinate of Team 2
id 9 is Subordinate of Team 2
id 10 is Subordinate of Team 2

By this you can Query any entry you want by simple determining the “parent_id” and “parent”

e.g.:

//Just Heads of any Team:
SELECT * FROM Team_Sub WHERE (parent = 1)

//Just Head of a specific team:
SELECT * FROM Team_Sub WHERE (parent = 1) AND (parent_id="team id")

//Just Subordinates of any Team:
SELECT * FROM Team_Sub WHERE (parent = 0)

//Just Subordinates of a specific team:
SELECT * FROM Team_Sub WHERE (parent = 0) AND (parent_id="team id")

//Just Anybody of a specific team:
SELECT * FROM Team_Sub WHERE (parent_id="team id")

*FYI : if not yet any dependencies on the value-names, id recommend to rename “parent” to “head_of_team” and “parent_id” to “team_id”*