Ashutosh Bapat <ashutosh(dot)bapat(at)enterprisedb(dot)com> writes:
> In order to test various cases of LATERAL join in Postgres-XC, I am trying
> to find a query where RelOptInof->lateral_relids would get set for plain
> base relations.
I think you need a lateral reference in a function or VALUES FROM-item.
As you say, plain sub-selects are likely to get flattened. (Possibly
if you stuck in a flattening fence such as OFFSET 0, you could get the
case to happen with a sub-select FROM item, but I'm too lazy to check.)
regards, tom lane