CYPHER 25
LOAD CSV WITH HEADERS FROM 'file:///persons.csv' AS row
CALL (row) {
  MERGE (p:Person {id: row.id})
  ON CREATE SET
    p.name       = row.name,
    p.age        = toIntegerOrNull(row.age),
    p.score      = toFloatOrNull(row.score),
    p.active     = toBoolean(row.active),
    p.born       = CASE WHEN row.born IS NOT NULL AND row.born <> '' THEN date(row.born) ELSE null END,
    p.createdAt  = datetime()
  ON MATCH SET
    p.updatedAt  = datetime()
} IN TRANSACTIONS OF 10000 ROWS
  ON ERROR CONTINUE
  REPORT STATUS AS s
RETURN s.transactionId, s.committed, s.errorMessage

CYPHER 25
LOAD CSV WITH HEADERS FROM 'file:///knows.csv' AS row
CALL (row) {
  MATCH (a:Person {id: row.fromId})
  MATCH (b:Person {id: row.toId})
  MERGE (a)-[:KNOWS {since: toIntegerOrNull(row.year)}]->(b)
} IN TRANSACTIONS OF 5000 ROWS
  ON ERROR CONTINUE
  REPORT STATUS AS s

CYPHER 25
LOAD CSV WITH HEADERS FROM 'file:///data.tsv' AS row FIELDTERMINATOR '\t'
CALL (row) { MERGE (p:Person {id: row.id}) }
IN TRANSACTIONS OF 10000 ROWS ON ERROR CONTINUE

LOAD CSV WITH HEADERS FROM 'file:///archive.csv.gz' AS row ...

linenumber()   // current line number — use as fallback ID
file()         // absolute path of file being loaded

CALL (row) {
  // write logic
} IN [n CONCURRENT] TRANSACTIONS
  [OF batchSize ROW[S]]
  [ON ERROR {CONTINUE | BREAK | FAIL | RETRY [FOR duration SECONDS] [THEN {CONTINUE|BREAK|FAIL}]}]
  [REPORT STATUS AS statusVar]

CYPHER 25
LOAD CSV WITH HEADERS FROM 'file:///large.csv' AS row
CALL (row) {
  MERGE (p:Person {id: row.id}) SET p.name = row.name
} IN 4 CONCURRENT TRANSACTIONS OF 5000 ROWS
  ON ERROR RETRY FOR 30 SECONDS THEN CONTINUE
  REPORT STATUS AS s

neo4j-admin database import full \
  --nodes=Person="persons_header.csv,persons.csv" \
  --nodes=Movie="movies_header.csv,movies.csv" \
  --relationships=ACTED_IN="acted_in_header.csv,acted_in.csv" \
  --relationships=DIRECTED="directed_header.csv,directed.csv" \
  --delimiter=, \
  --id-type=STRING \
  --bad-tolerance=0 \
  --threads=$(nproc) \
  --high-parallel-io=on \
  neo4j

neo4j-admin database import full --dry-run ...

undefined

undefined

| Field | Meaning |
|---|---|
| `:ID` | Unique ID for relationship wiring (not stored as property by default) |
| `:ID(Group)` | Scoped ID space — use when node types share IDs |
| `:LABEL` | One or more labels; semicolon-separated: `Person;Employee` |
| `prop:int` | Typed property; types: `int long float double boolean byte short string` |
| `prop:date` | Temporal: `date localtime time localdatetime datetime duration` |
| `prop:int[]` | Array — semicolon-separated values in cell: `1;2;3` |
| `prop:vector` | Float vector (2025.10+) — semicolon-separated coordinates |

undefined

undefined

`:START_ID` / `:END_ID` must reference the same `:ID` group as the node files.

neo4j-admin database import full \
  --format=block \
  --schema=schema.cypher \
  --nodes=Person="persons_header.csv,persons.csv" \
  neo4j

// schema.cypher
CREATE CONSTRAINT person_id IF NOT EXISTS FOR (n:Person) REQUIRE n.id IS UNIQUE;
CREATE CONSTRAINT movie_id  IF NOT EXISTS FOR (n:Movie)  REQUIRE n.id IS UNIQUE;
CREATE RANGE INDEX person_email IF NOT EXISTS FOR (n:Person) ON (n.email);
CREATE TEXT  INDEX movie_title  IF NOT EXISTS FOR (n:Movie)  ON (n.title);

undefined

Requires Enterprise Edition + `block` store format.

---

CALL apoc.periodic.iterate(
  "MATCH (p:Person) WHERE NOT (p)-[:HAS_ACCOUNT]->() RETURN p",
  "CREATE (p)-[:HAS_ACCOUNT]->(a:Account {id: randomUUID()})",
  {batchSize: 10000, parallel: false, retries: 2}
) YIELD batches, total, errorMessages
RETURN batches, total, errorMessages

CALL apoc.load.csv('file:///persons.csv', {
  header: true,
  sep: ',',
  skip: 1,
  limit: 1000000
}) YIELD lineNo, map, list
CALL (map) {
  MERGE (p:Person {id: map.id}) SET p.name = map.name
} IN TRANSACTIONS OF 10000 ROWS ON ERROR CONTINUE

CALL apoc.load.json('https://api.example.com/persons') YIELD value
CALL (value) {
  MERGE (p:Person {id: value.id}) SET p.name = value.name
} IN TRANSACTIONS OF 1000 ROWS ON ERROR CONTINUE

// Row counts per label
MATCH (n:Person) RETURN count(n) AS persons;
MATCH ()-[:KNOWS]->() RETURN count(*) AS knows_rels;

// After import: create additional non-unique indexes (populated async)
CREATE TEXT INDEX movie_title IF NOT EXISTS FOR (n:Movie) ON (n.title);
CREATE RANGE INDEX person_born IF NOT EXISTS FOR (n:Person) ON (n.born);

// Poll population — wait until populationPercent = 100 before opening to queries
SHOW INDEXES YIELD name, state, populationPercent
WHERE state <> 'ONLINE' OR populationPercent < 100
RETURN name, state, populationPercent
ORDER BY populationPercent;

// Spot check: null keys = import bug
MATCH (p:Person) WHERE p.id IS NULL RETURN count(p) AS missing_id;