The flag EXCLUDE DELETED FLAG is useful in combination with PARALLEL MODE to obtain a variant of the deter- ministic parallel mode where a node is deleted at most once. Namely, when the execution of the right-hand side for a match leads to the deletion of a node, this is remembered, and this node is excluded from the set of candidates for further matches in the query state (i. e., the method excludeFromMatch of the query state returns true for such nodes).

In effect, this means that the first match which deletes a node is used and all further possible matches are disabled.