>>>>> "Tom" == Tom Lane <tgl@sss.pgh.pa.us> writes:
>> What I'm wondering is whether the param in the copied estate
>> shouldn't rather be just a proxy for the one in the original estate
>> - if we need to evaluate it, then do so in the original estate,
>> store the value there, and copy the value back into the EPQ
>> plantree.
Tom> Don't think that's going to work; the EPQ environment doesn't have
Tom> any way to know that an execPlan link is pointing to something in
Tom> a different estate.
But can't such a way be created? e.g. by pointing execPlan to a special
proxy node that points back to the original estate?
Tom> Your other idea of forcing initPlan parameters to be evaluated
Tom> before we enter the EPQ execution environment is probably more
Tom> workable. It would be annoying to do that for every initPlan in
Tom> sight, but I think we could look at the subplan's extParam to see
Tom> whether it potentially references that parameter. (Although
Tom> really, in most scenarios it wouldn't matter because all the
Tom> initPlans in a data-modifying query are probably referenced in the
Tom> subplan anyhow ...)
Well, the case of UPDATE ... SET foo = case when x then (select thing
from big_cte) else (select thing from other_big_cte) end will be rather
annoying if we end up forcing both initplans to execute.
--
Andrew (irc:RhodiumToad)
