how to generate missing records in a join

[skyline01]

I have table Tickets like:

Tickets:
Load * Inline [
TicketID, ChangeID
1, 10
2, 20
3,
4, 40
5,
6, 60
7, 60
8, 80
9, 90
]
;

Not all tickets have an associated change.  Every ticket will have at most 1 associated change.  A given change can be associated with 1+ tickets.

I have table Change_Impacted_Locations, like:

Change_Impacted_Locations:
Load * Inline [
ChangeID, Location
10, a
40, b
40, c
60, d
60, e
90, a
]
;

Not every change will have a location impacted record.  A change can impact 1+ locations.  Naturally, a location can be associated with 1+ locations.

I need to append a dummy record to my Change_Impacted_Locations table for all distinct ChangeIDs (where populated) on the Tickets  table.  So, I need to generate something like:

Missing_Locations:
Load * Inline [
ChangeID, Location
20, dummy
80, dummy
]
;

And, I need these records concatenated into my Change_Impacted_Locations table.

How can I achieve this?

[skyline01 · Accepted solution]

I figured out the solution to my problem.

//need ChangeID name to be distinct
Tickets:
Load * Inline [
TicketID, ChangeID on Tickets
1, 10
2, 20
3,
4, 40
5,
6, 60
7, 60
8, 80
9, 90
]
;

//need ChangeID name to be distinct
Change_Impacted_Locations:
Load * Inline [
ChangeID on Impacted Locations, Location
10, a
40, b
40, c
60, d
60, e
90, a
]
;

//will autoconcatenate to the Change_Impacted_Locations table
Load
	"ChangeID on Tickets" as "ChangeID on Impacted Locations"
	,'dummy' as Location
Resident
	Tickets
Where
	Not Exists("ChangeID on Impacted Locations", "ChangeID on Tickets")
;