You can easily create test data to help debug SQL statements:
with data (key, value) as
( values ('key1', 'a')
, ('key2', null)
, ('key3', 'z')
)
select 'min', min(coalesce(value,'')) from data
union
select 'max', max(coalesce(value,'')) from dataYou or someone you know looking to buy or sell?
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