Return Missing Records Over Multiple Tables. Query Challenge!

I have received some data out of a relational database that is incomplete and I need to find where the holes are. Essentially, I have three tables. One table has a primary key of PID. The other two tables have PID as a foreign key. Each table should have at least one instance of every available PID.

I need to find out which ones are in the second and third table that do not show up in the first one,
which ones are in the first and third but not in the second,
and which ones are in the first and second but not in the third.

I've come up with quite a few ways of working it but they all involve multiple union statements (or dumping to temp tables) that are joining back to the original tables and then unioning and sorting the results. It just seems like there should be a clean elegant way to do this.

Here is an example:



create table TBL1(PID int, info1 varchar(10) )

Create table TBL2(TID int,PID int)

Create table TBL3(XID int,PID int)


insert into TBL1

select '1','Someone' union all

select '2','Will ' union all

select '4','Have' union all

select '7','An' union all

select '8','Answer' union all

select '9','ForMe'





insert into TBL2

select '1','1' union all

select '2','1' union all

select '3','8' union all

select '4','2' union all

select '5','3' union all

select '6','3' union all

select '7','5' union all

select '8','9'


insert into TBL3

select '1','10' union all

select '2','10' union all

select '3','8' union all

select '4','6' union all

select '5','7' union all

select '6','3' union all

select '7','5' union all

select '8','9'

I need to find the PID and the table it is missing from. So the results should look like:








PID
MISSING FROM

1
TBL3

2
TBL3

3
TBL1

4
TBL2

4
TBL3

5
TBL1

6
TBL1

6
TBL2

7
TBL2

10
TBL1

10
TBL2



Thanks all.