Re: why partition pruning doesn't work? - Mailing list pgsql-hackers

On 2018/06/06 14:10, David Rowley wrote:
> I then decided that
> I didn't like the way we need to check which params are in the Expr
> each time we call partkey_datum_from_expr. It seems better to prepare
> this in advance when building the pruning steps. I started work on
> that, but soon realised that I'd need to pass a List of Bitmapsets to
> the executor. This is a problem as Bitmapset is not a Node type and
> cannot be copied with COPY_NODE_FIELD(). Probably this could be
> refactored to instead of passing 3 Lists in the PartitionPruneStepOp
> we could invent a new node type that just has 3 fields and store a
> single List.

I wonder why we need to create those Bitmapsets in the planner?  Why not
in ExecSetupPartitionPruneState()?  For example, like how
context->exprstates is initialized.

Thanks,
Amit