execution state trees, and ExecEvalExpr takes an expression state tree
not an expression plan tree. The plan tree is now read-only as far as
the executor is concerned. Next step is to begin actually exploiting
this property.
to plan nodes, not vice-versa. All executor state nodes now inherit from
struct PlanState. Copying of plan trees has been simplified by not
storing a list of SubPlans in Plan nodes (eliminating duplicate links).
The executor still needs such a list, but it can build it during
ExecutorStart since it has to scan the plan tree anyway.
No initdb forced since no stored-on-disk structures changed, but you
will need a full recompile because of node-numbering changes.
> moment, but they used to be used; I think the correct response is to
> put back the missing counter increments, not rip out the counters.
Ok, fair enough. It's worth noting that they've been broken for a
while -- for example, the HashJoin counter increments were broken when
you comitted r1.20 of executor/nodeHashJoin.c in May of '99.
I've attached a revised patch that doesn't remove the counters (but
doesn't increment them either: I'm not sure of all the places where
the counter should be incremented).
Neil Conway
Tom Lane
Bruce Momjian