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create table tableA(Name varchar(20), City varchar(20));
insert into tableA values
('Paulo','Rome')
,('Rudy','Singapore')
,('Ming','Singapore')
,('Takeshi','Tokyo')
,('Judy','Jakarta')
,('Yuki','Tokyo')
,('Steve','Singapore')
;
select * from tableA;
| Name | City |
|---|---|
| Paulo | Rome |
| Rudy | Singapore |
| Ming | Singapore |
| Takeshi | Tokyo |
| Judy | Jakarta |
| Yuki | Tokyo |
| Steve | Singapore |
select case when count(*)=3 then 'true' else 'false' end res
from (
select *,
row_number() over (partition by city order by name) as rn
from tableA
where city in ('Berlin', 'Tokyo', 'Singapore')
) a
where rn = 1
| res |
|---|
| false |
select case when count(*)=3 then 'true' else 'false' end res
from(
select distinct city
from tableA
where city in ('Berlin', 'Tokyo', 'Singapore')
) a
| res |
|---|
| false |