Unloads the nodes: they leave the model outright, along with the expansion bookkeeping that would
otherwise keep the graph remembering ids it will never be asked about again.
Unlike removeNodes this leaves no tombstone, so a subsequent read of a released relation
expands it afresh rather than resolving to an emptied node.
Unloads the nodes: they leave the model outright, along with the expansion bookkeeping that would otherwise keep the graph remembering ids it will never be asked about again.
Unlike removeNodes this leaves no tombstone, so a subsequent read of a released relation expands it afresh rather than resolving to an emptied node.