THE FILE FIELD GUIDE

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Apache Arrow Data

Data & Science

ARROW commonly denotes Arrow IPC data. IPC has sequential stream and random-access file formats; readers are not interchangeable. Identify the producer format/schema before choosing a reader.

What it is used for: Exchange of typed column data and record batches
What the file contains: Binary data

All sections, questions and sources

Content reviewed：2026-10-12 · Editor：Kai

Opening steps

Choose your environment or purpose to see its steps.

Identify IPC file versus stream

The name alone does not select the reader.

Ask the writer which IPC framing was used.
Choose open_file/open_stream or the matching reader.
Inspect schema and record batches.

Read in batches

Avoid expanding large data all at once.

Inspect names, types and batch information.
Read required batches in sequence.
Compare cumulative rows and representative values.

Deliver to another analysis environment

Inspect extension-type and compression support.

Confirm destination framing and data types.
Export separately through a compatible library.
Compare types, dictionary values, nulls and total rows.

Menu labels and support vary by app, OS and version. Preserve the original before making changes.

Troubleshooting by symptom

File reader fails: check stream format or incomplete transfer.
Missing rows: inspect batch handling and selected range.
Memory growth: distinguish zero-copy reads from allocating table conversions.
File reader rejects it: inspect stream/file framing mismatch.
Only some data appears: inspect complete batch iteration and transfer.
Unsupported type: inspect extension/compression and library requirements.

Arrow IPC → Parquet / CSV

Read the required batches with the correct reader; record schema/counts.
Use a suitable exporter and compare nulls, nested data and timestamps.
Communicate framing/schema and validate counts across all batches.

Stream/file conversion requires reading and rewriting; CSV does not retain equivalent types/batch structure.

File and stream reading methods

A reader expecting file framing/footer can reject a stream; identify the producer’s framing.

Source for these steps：Apache Software Foundation · Streaming, Serialization, and IPC / Apache Software Foundation · Feather File Format

Validate types and the complete batch sequence

The first readable batch does not establish completeness; total required rows.

Dictionary/extension types can change during conversion; preserve values and schema.

Source for these steps：Apache Software Foundation · Streaming, Serialization, and IPC / Apache Software Foundation · Feather File Format

Related-format differences

Related-format differences
Format	Main role	What to check
IPC file	File-framed IPC	File reader
IPC stream	Sequential IPC batches	Stream reader
Feather V2	Uses IPC file framing	Different from V1

Handling and security

Preserve originals/schema descriptions and review size; follow producer specifications for unrelated ARROW uses.

Questions and answers

Are file and stream identical?

Access patterns and readers differ.

Does the suffix determine the reader?

Confirm how it was written.

Does zero-copy require no memory?

Subsequent processing/conversion may still allocate.

Is Arrow plain text like CSV?

IPC is structured binary data requiring a compatible reader.

Can I rename Arrow to Feather?

V2 relates to IPC file framing, but streams and V1 differ.

Format facts: name, steward and MIME type

Formal name: Apache Arrow IPC file or stream (common .arrow use)
Steward / specification: Apache Software Foundation
MIME type: Depends on the producer or server; an extension alone does not establish a MIME type.

Primary and official sources

Project documentationStreaming, Serialization, and IPC
Distinguishes IPC stream and file readers.
Apache Software Foundation · Link checked：2026-10-12
Project documentationFeather File Format
Explains Feather V2, Arrow IPC, compression and legacy format.
Apache Software Foundation · Link checked：2026-10-12