WHERE clause vs JOIN condition

join-vs-where.sql

# Good: Filtering in the WHERE clause

...
SELECT cnv.email, 
            cnv.created_at AS expressed_interest_at 
FROM helpscout.conversation AS cnv 
   JOIN helpscout.conversation_tag AS ctg 
      ON cnv.id = ctg.conversation_id
WHERE ctg.tag = 'beacon-interest'
...

# Good: Including it in the join condition

...
select conv.email,  conv.created_at as expressed_interest_at
from helpscout.conversation conv
join helpscout.conversation_tag tag
on conv.id = tag.conversation_id and tag.tag = 'beacon-interest'
...