I'm trying to execute one sql query using joins, but I'm getting the below error:
ORA-00979: not a GROUP BY expression
00979. 00000 - "not a GROUP BY expression"
The query is to count the number of normalized_event_ids along with the error message and error_ids using two tables.:
select count(nee.normalised_event_id),
em.error_message,
em.error_message_id
from normalised_event_error nee, error_message em
where nee.charge_start_date >= to_date('01-07-2017','DD-MM-YYYY')
and nee.error_message_id = em.error_message_id
group by em.error_message;