<div dir="ltr">On further thought, I think we need to restrict the join pushdown only for outer joins. Only those joins
canproduce NULL rows. If we go with that change, we will need my changes as well and a testcase with inner join.<br
/></div><divclass="gmail_extra"><br /><div class="gmail_quote">On Tue, Jun 7, 2016 at 6:19 PM, Amit Langote <span
dir="ltr"><<ahref="mailto:amitlangote09@gmail.com" target="_blank">amitlangote09@gmail.com</a>></span> wrote:<br
/><blockquoteclass="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Tue, Jun 7,
2016at 7:47 PM, Ashutosh Bapat wrote:<br /><span class="">> On Tue, Jun 7, 2016 at 4:07 PM, Amit Langote wrote:<br
/>>> On 2016/06/07 19:13, Ashutosh Bapat wrote:<br /></span><span class="">>> > So, your patch looks to
bethe correct approach (even after we support<br /> >> > deparsing subqueries). Can you please include a test
inregression?<br /> >><br /> >> I added a slightly modified version of your test to the originally
posted<br/> >> patch.<br /> >><br /> > Looks good to me. If we add a column from the outer relation, the
"NULL"ness<br/> > of inner column would be more clear. May be we should tweak the query to<br /> > produce few
morerows, some with non-NULL columns from both the relations.<br /> > Also add a note to the comment in the test
mentioningthat such a join won't<br /> > be pushed down for a reader to understand the EXPLAIN output. Also, you<br
/>> might want to move that test, closer to other un-pushability tests.<br /><br /></span>Done in the attached.
Pleasecheck if my comment explains the reason<br /> of push-down failure correctly.<br /><br /> Thanks,<br /> Amit<br
/></blockquote></div><br/><br clear="all" /><br />-- <br /><div class="gmail_signature"
data-smartmail="gmail_signature"><divdir="ltr">Best Wishes,<br />Ashutosh Bapat<br />EnterpriseDB Corporation<br />The
PostgresDatabase Company<br /></div></div></div>