Amit Langote <langote_amit...@lab.ntt.co.jp> writes:
> On 2019/03/23 6:07, Tom Lane wrote:
>> I also feel like you used a dartboard while deciding where to insert the
>> call in query_planner(); dropping it into the middle of a sequence of
>> equivalence-class-related operations seems quite random. Maybe we could
>> delay that step all the way to just before make_one_rel, since the other
>> stuff in between seems to only care about baserels? For example,
>> it'd certainly be better if we could run remove_useless_joins before
>> otherrel expansion, so that we needn't do otherrel expansion at all
>> on a table that gets thrown away as being a useless join.
> create_lateral_join_info() expects otherrels to be present to propagate
> the information it creates.
Sure, but the actually-useful work in that function is just concerned
with baserels. The only thing it does with otherrels is to propagate
parents' lateral-ref info to children, which is a lot easier, cheaper,
and more reliable if we let build_simple_rel do it. See the version
of 0001 I just pushed.
I'll look at 0003 and up tomorrow.
regards, tom lane
