select SF.customer_email , SF.created_at
YEAR(TO_DATE(SF.created_at)) = '2016'
MONTH(TO_DATE(SF.created_at)) = '6'
NOT IN (
select SFO.customer_email FROM Table1 SFO
TO_DATE(SFO.created_at) < '2016-05-31'
I have checked manually and I should get results for the query but it returns empty result set.
Note: I am using same table in the sub-query as well. Just a different condition on date column.