Neo4j constraints enforce uniqueness, existence, type, and keys

The constraints chapter lists four families: uniqueness of combined property values for a label or relationship type; existence of a property (Enterprise); required property types (Enterprise); and key constraints that combine existence and uniqueness (Enterprise). It points to create, show, and drop operations and to related syntax reference.

Teams loading or syncing graph data need these rules to keep integrity as writes accumulate. The manual notes that managing many individual constraints gets hard, and that not all types are available via older CREATE CONSTRAINT syntax.

Preferring a graph type as the schema definition treats shape—labels, types, keys, types—as one governed model. That shared shape is what interoperable tools and agents can validate against across the graph database.