On 17/05/2020 at 04:22, Tom Lane wrote:> Note that you're not really
getting the same plan that way: it's not
a left join anymore, because you put a strict constraint on the join's
inner relation, so the planner realizes it doesn't have to produce any
null-extended rows. You could make it work with the desired semantics
with something along the lines of
SELECT * FROM tbl1 t1
LEFT JOIN (select * from tbl2 where tbl2.date >= '2019-04-21') t2
USING (date)
WHERE t1.date >= '2019-04-21';
but of course that's even less easy :-(
Thanks, I didn't realise my version of the query was incorrect.
It seems like there isn't much hope of creating a view equivalent to the
query which would behave reasonably with "date >= CONST" constraint, or
am I missing something? I think I can create a workaround using
functions but would love to know if there's something simpler I could do.
Thanks,
Lukasz
