Indexes and Constraints

Indexes and constraints are essential for performance and data integrity in Neo4j. Indexes speed up queries by avoiding full graph scans, while constraints enforce rules about your data.

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Why Indexes Matter

Without indexes, Neo4j must scan every node with a given label to find matches:

// Without an index, this scans ALL Person nodes
MATCH (p:Person {email: "alice@example.com"})
RETURN p

With an index on :Person(email), Neo4j goes directly to the matching node.

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Types of Indexes

Index Type	Purpose	Example
Range index	General-purpose lookups, ranges, sorting	Equality, >, <, STARTS WITH
Text index	Full-text string matching	CONTAINS, ENDS WITH
Point index	Geospatial queries	Distance and bounding-box queries
Composite index	Multi-property lookups	Queries filtering on multiple properties
Full-text index	Advanced text search with scoring	Fuzzy matching, relevance ranking
Lookup index	Internal label/type lookups	Automatic — do not create manually

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Creating Indexes

Range index (most common)

// Index on a single property
CREATE INDEX person_email FOR (p:Person) ON (p.email)

// Index on a relationship property
CREATE INDEX purchased_date FOR ()-[r:PURCHASED]-() ON (r.date)

Composite index

CREATE INDEX person_name_age FOR (p:Person) ON (p.name, p.age)

Text index

CREATE TEXT INDEX person_name_text FOR (p:Person) ON (p.name)

Text indexes support CONTAINS and ENDS WITH queries efficiently.

Point index

CREATE POINT INDEX location_idx FOR (p:Place) ON (p.location)

Full-text index

CREATE FULLTEXT INDEX product_search FOR (p:Product) ON EACH [p.name, p.description]

Query full-text indexes using db.index.fulltext.queryNodes:

CALL db.index.fulltext.queryNodes("product_search", "wireless mouse") YIELD node, score
RETURN node.name, score
ORDER BY score DESC

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Managing Indexes

List all indexes

SHOW INDEXES

Drop an index

DROP INDEX person_email

Check index usage with EXPLAIN

EXPLAIN MATCH (p:Person {email: "alice@example.com"})
RETURN p

Look for NodeIndexSeek in the query plan — this confirms the index is being used.

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Constraints

Constraints enforce data integrity rules in your graph: