Batched subqueries and logical interchange

LOAD CSV WITH HEADERS FROM $file AS row
CALL {
  WITH row
  CALL apoc.merge.node(['Person'], {id: toInteger(row.id)}, {name: row.name})
} IN TRANSACTIONS OF 1000 ROWS;

CALL { ... } IN TRANSACTIONS [OF size ROWS] runs on the implicit/autocommit path, defaults to 1000 rows and accepts a parameterised size. Each batch commits independently. A failure rolls back its current batch; earlier batches remain committed. Explicit transactions, nested batching, multiple batched subqueries, UNION and writes outside the batch are refused. This implementation uses the CALL { WITH ... } import syntax, not the newer CALL (variables) { ... } form. Parallel/concurrent batches and ON ERROR policies are not implemented.

A direct LOAD CSV ... CALL {...} IN TRANSACTIONS streams records with only a batch of bindings retained. UNWIND retains its input list but does not build all row bindings at once. More complex prefixes are materialised. A trailing RETURN/WITH may materialise output rows. The server's exclusive write gate is held for the statement; batching improves memory/durability boundaries, not concurrent write execution.

apoc.load.json(source[, path, config]) loads a JSON object, scalar or array (one result row per array item). Only empty path/config are accepted.
apoc.import.json(source[, config]) imports APOC node/relationship JSON or JSONL, remapping exported string IDs. It is one atomic statement, not a streaming batched import. Only empty configuration is supported.
apoc.export.json.all(file, {stream: true}) exports APOC-style JSONL and yields data; JSON temporal/point conversion follows the existing JSON encoder.
apoc.export.cypher.all(file, {stream: true}) yields cypherStatements, a logical data export preserving labels, relationships, scalar/list/map, temporal and point properties. Bytes and non-finite numbers are refused. Schema/index export and APOC export-format/batching options are not included.

Use a null filename and {stream:true} to return export text without creating a file. File exports create a new file and never overwrite one; filesystem effects are not rolled back with graph transactions. Imports/loaders accept the same local/file/plain-HTTP sources as LOAD CSV; HTTPS and JSONPath remain unsupported. Both export formats currently materialise their text in memory. The existing gdb.cypher.import(path) loads the generated Cypher script.

The deprecated apoc.periodic.iterate interface is intentionally not added; native batching provides the requested import capability.

Backup, restore and transfer · Transactions and concurrency · Server configuration

Batched subqueries and logical interchange

Batched subqueries and logical interchange

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