Question

For example, I have a table tbl like

values
10
20
30
40

on this table by the condition I have GROUP BY like this:

SELECT ???
FROM tbl 
GROUP BY values

I need to check that group has some value, for example 30

UPD:
In real task a have a table with many columns and other operations on them and in one column i need to check whether value in every group of this column.

UPD2:
I need something like this:

select 
min(created_timestamp),
max(resource_id),
max(price),
CASE WHEN event_type has (1704 or 1701 or 1703) THEN return found value END
CASE WHEN event_type has (1707) THEN return 1707 END
from subscriptions
group by guid

Answer 1

SELECT
    MIN(created_timestamp),
    MAX(resource_id),
    MAX(price),
    MIN(CASE WHEN event_type IN (1704, 1701, 1703) 
                 THEN found_value 
             WHEN event_type = 1707 
                 THEN 1707 
                 ELSE NULL 
        END)
FROM subscriptions
GROUP BY guid ;