greatfung :
I would like to have a table able to store team specific values, if no record found, the default record will be returned.
TableName: Products
ProdID ProdName Team
1 AAA <NULL>
1 AAA_T1 T1
2 BBB <NULL>
3 CCC <NULL>
3 CCC_T1 T1
3 CCC_T2 T2
4 DDD <NULL>
4 DDD_T3 T3
For the query, Team will need to pass in, all Products will be returned.
Team T1
ProdID ProdName
1 AAA_T1
2 BBB
3 CCC_T1
4 DDD
Team T2
ProdID ProdName
1 AAA
2 BBB
3 CCC_T2
4 DDD
Team T3
ProdID ProdName
1 AAA
2 BBB
3 CCC
4 DDD_T3
How do I achieve this? Do I need to change the table structure?
forpas :
With NOT EXISTS:
select distinct p.prodname
from products p
where p.team = 'T1'
or (
p.team is null
and not exists (
select 1 from products
where prodid = p.prodid and team = 'T1'
)
)
You may remove distinct if there are no duplicates.
See the demo.
Or with conditional aggregation:
select max(case when team = 'T1' or team is null then prodname end) prodname
from products
group by prodid
See the demo.
Results:
> | prodname |
> | :------- |
> | AAA_T1 |
> | BBB |
> | CCC_T1 |
> | DDD |
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