relationship from parent to child or self-join

J

Janis

tblArea
AreaID
area



tblHeadEnd
HeadEndID
AreaID
headend

tblRouter
RouterID
HeadEndID
router

tblPorts
PortID
RouterID

tblTransmitter
TransmitterID
PortID
transmitter
PortID
RouterID

tblNodes
NodeID
transmitterID


tblNodeNamesID
NodeID
ParentNodeName
date created

tblUtilization
utilID
NodeID
percentage
Date

There are nodes that divide when the utilization is over 50%. They might
have the name ABCD and when it divides it will have two new nodes ABCD-A and
ABCD-B. Then one will get moved to a new transmitter. I have the date
created in nodes and the parentnode. On my weekly report I need to still
show the parent node even if there is no
utilization.

How do I relate the parent node to the two new nodes in my table structure?
So if I have a relationship from ParentNodeName to NodeID this would be a
self join? but it would show the old name ABCD and the related two new childs
ABCD-A and ABCD-B? assuming I can figure out how to do the data input to show
the move.

tia,
 
K

KARL DEWEY

I see one error in that tblTransmitter has field PortID twice.

I could not follow all of your table relationships. Try to use the
Employee-Spuervisor relationship as below.
TblEmployee --
EmpID - primary key
Name
Supervisor - this is a foreign key

John Smith - EmpID - 4001
Supervisor - 1005
Bill Jones - EmpID - 4022
Supervisor - 4001

To do this you place the Employee table in the relationship window twice and
create a one-to-many relation between TblEmployee, field EmpID and
TblEmployee_1, field Supervisor.
 
J

Janis

So it is just a self-join. To show the parent node and the child nodes
divided from the parent? okay, thanks
 
J

Janis

you probably can't follow my relationships because the data is hard to
understand.
 

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