Query and Join help please

[hensa22]

try this,

select jobs_id,a.addr_atyp_code,addr_street_line1 
from jobs a
left join addr b  on   a.jobs_id = b.addr_id 
where 
jobs_status = 'A' 
and (a.addr_atyp_code = 'MA'  or b.addr_id is null)
and jobs_effective_date = (select max(b.jobs_effective_date) from jobs b where b.jobs_pidm = a.jobs_pidm)

I assume field addr_id on table addr is foreign key references jobs_id on table jobs.

one more thing, alias 'a' duplicate in your first post.
maybe if you post table structure it would be great help