WHERE and FILTER

WHERE attaches a predicate to MATCH or SELECT. FILTER filters the current working table; FILTER WHERE is an accepted spelling. Only true passes: false and unknown/null do not.

MATCH (p:Person) WHERE p.age >= 30
FILTER p.name <> 'Bob'
RETURN p.name AS name;

The result is Alice. Predicates can use bound properties, parameters, scalar operators and the supported element predicates.

An OPTIONAL MATCH predicate participates in matching before null padding. A later FILTER runs after padding and can remove unmatched rows. Put conditions on the optional neighbor inside OPTIONAL MATCH when you want to keep input rows that have no such neighbor.

For path selectors, a MATCH-level WHERE is applied after selection; an inline pattern predicate restricts candidates before selection. This can change shortest-path results. See selectors.