pgsql: Use the correct tuplestore read pointer in a NamedTuplestoreScan

Use the correct tuplestore read pointer in a NamedTuplestoreScan. Tom Kazimiers reported that transition tables don't work correctly when they are scanned by more than one executor node. That's because commit 18ce3a4ab allocated separate read pointers for each executor node, as it must, but faile

pgsql: Use the correct tuplestore read pointer in a NamedTuplestoreScan

Use the correct tuplestore read pointer in a NamedTuplestoreScan. Tom Kazimiers reported that transition tables don't work correctly when they are scanned by more than one executor node. That's because commit 18ce3a4ab allocated separate read pointers for each executor node, as it must, but faile