आप group by building, location
. कर सकते हैं पंक्तियों के लिए where object in ('WALL', 'WINDOW')
:
select building, location, 'FLAG' action
from tablename
where object in ('WALL', 'WINDOW')
group by building, location
having count(distinct object) < 2
शर्त count(distinct object) < 2
having
. में खंड building, location
. का संयोजन देता है जहां 'WALL'
और 'WINDOW'
दोनों मौजूद नहीं हैं।
डेमो
देखें। .
परिणाम:
| building | location | action |
| -------- | -------- | ------ |
| A | FLOOR2 | FLAG |
| B | FLOOR1 | FLAG |
या मौजूद नहीं है:
select t.building, t.location, 'FLAG' action
from tablename t
where object in ('WALL', 'WINDOW')
and not exists (
select 1 from tablename
where building = t.building and location = t.location and object <> t.object
)
डेमो देखें ।