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README.md

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+---
+language:
+  - en
+  - mul
+license: cc0-1.0
+task_categories:
+  - text-generation
+  - feature-extraction
+  - text-classification
+pretty_name: Open Library
+tags:
+  - books
+  - library
+  - bibliography
+  - open-library
+  - openlibrary
+  - isbn
+size_categories:
+  - 100M+
+configs:
+  - config_name: authors
+    data_files:
+      - split: train
+        path: data/authors/*.parquet
+  - config_name: works
+    data_files:
+      - split: train
+        path: data/works/*.parquet
+  - config_name: editions
+    data_files:
+      - split: train
+        path: data/editions/*.parquet
+    default: true
+  - config_name: ratings
+    data_files:
+      - split: train
+        path: data/ratings/*.parquet
+  - config_name: reading-log
+    data_files:
+      - split: train
+        path: data/reading-log/*.parquet
+  - config_name: redirects
+    data_files:
+      - split: train
+        path: data/redirects/*.parquet
+  - config_name: deletes
+    data_files:
+      - split: train
+        path: data/deletes/*.parquet
+  - config_name: lists
+    data_files:
+      - split: train
+        path: data/lists/*.parquet
+  - config_name: other
+    data_files:
+      - split: train
+        path: data/other/*.parquet
+  - config_name: covers_metadata
+    data_files:
+      - split: train
+        path: data/covers_metadata/*.parquet
+  - config_name: wikidata
+    data_files:
+      - split: train
+        path: data/wikidata/*.parquet
+dataset_info:
+  - config_name: authors
+    features:
+      - name: key
+        dtype: string
+      - name: name
+        dtype: string
+      - name: alternate_names
+        dtype: string
+      - name: bio
+        dtype: string
+      - name: birth_date
+        dtype: string
+      - name: death_date
+        dtype: string
+      - name: date
+        dtype: string
+      - name: entity_type
+        dtype: string
+      - name: fuller_name
+        dtype: string
+      - name: personal_name
+        dtype: string
+      - name: title
+        dtype: string
+      - name: photos
+        dtype: string
+      - name: links
+        dtype: string
+      - name: remote_ids
+        dtype: string
+      - name: wikidata_id
+        dtype: string
+      - name: viaf_id
+        dtype: string
+      - name: isni
+        dtype: string
+      - name: source_records
+        dtype: string
+      - name: revision
+        dtype: int32
+      - name: created
+        dtype: string
+      - name: last_modified
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 15071242
+  - config_name: works
+    features:
+      - name: key
+        dtype: string
+      - name: title
+        dtype: string
+      - name: subtitle
+        dtype: string
+      - name: author_keys
+        dtype: string
+      - name: covers
+        dtype: string
+      - name: description
+        dtype: string
+      - name: notes
+        dtype: string
+      - name: subjects
+        dtype: string
+      - name: subject_places
+        dtype: string
+      - name: subject_people
+        dtype: string
+      - name: subject_times
+        dtype: string
+      - name: lc_classifications
+        dtype: string
+      - name: first_publish_date
+        dtype: string
+      - name: revision
+        dtype: int32
+      - name: created
+        dtype: string
+      - name: last_modified
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 40718247
+  - config_name: editions
+    features:
+      - name: key
+        dtype: string
+      - name: title
+        dtype: string
+      - name: subtitle
+        dtype: string
+      - name: author_keys
+        dtype: string
+      - name: work_keys
+        dtype: string
+      - name: isbn_10
+        dtype: string
+      - name: isbn_13
+        dtype: string
+      - name: lccn
+        dtype: string
+      - name: oclc_numbers
+        dtype: string
+      - name: ocaid
+        dtype: string
+      - name: identifiers
+        dtype: string
+      - name: local_id
+        dtype: string
+      - name: publishers
+        dtype: string
+      - name: publish_date
+        dtype: string
+      - name: publish_places
+        dtype: string
+      - name: publish_country
+        dtype: string
+      - name: edition_name
+        dtype: string
+      - name: by_statement
+        dtype: string
+      - name: contributions
+        dtype: string
+      - name: languages
+        dtype: string
+      - name: translated_from
+        dtype: string
+      - name: translation_of
+        dtype: string
+      - name: number_of_pages
+        dtype: int32
+      - name: pagination
+        dtype: string
+      - name: physical_format
+        dtype: string
+      - name: physical_dimensions
+        dtype: string
+      - name: weight
+        dtype: string
+      - name: covers
+        dtype: string
+      - name: description
+        dtype: string
+      - name: first_sentence
+        dtype: string
+      - name: notes
+        dtype: string
+      - name: table_of_contents
+        dtype: string
+      - name: subjects
+        dtype: string
+      - name: dewey_decimal_class
+        dtype: string
+      - name: lc_classifications
+        dtype: string
+      - name: genres
+        dtype: string
+      - name: series
+        dtype: string
+      - name: links
+        dtype: string
+      - name: source_records
+        dtype: string
+      - name: copyright_date
+        dtype: string
+      - name: other_titles
+        dtype: string
+      - name: work_titles
+        dtype: string
+      - name: classifications
+        dtype: string
+      - name: revision
+        dtype: int32
+      - name: created
+        dtype: string
+      - name: last_modified
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 55615769
+  - config_name: ratings
+    features:
+      - name: work_key
+        dtype: string
+      - name: edition_key
+        dtype: string
+      - name: rating
+        dtype: int32
+      - name: date
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 599849
+  - config_name: reading-log
+    features:
+      - name: work_key
+        dtype: string
+      - name: edition_key
+        dtype: string
+      - name: shelf
+        dtype: string
+      - name: date
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 11778241
+  - config_name: redirects
+    features:
+      - name: key
+        dtype: string
+      - name: location
+        dtype: string
+      - name: type_name
+        dtype: string
+      - name: revision
+        dtype: int32
+      - name: last_modified
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 1697861
+  - config_name: deletes
+    features:
+      - name: key
+        dtype: string
+      - name: type_name
+        dtype: string
+      - name: revision
+        dtype: int32
+      - name: last_modified
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 3717514
+  - config_name: lists
+    features:
+      - name: key
+        dtype: string
+      - name: name
+        dtype: string
+      - name: description
+        dtype: string
+      - name: seeds
+        dtype: string
+      - name: seed_count
+        dtype: int32
+      - name: revision
+        dtype: int32
+      - name: created
+        dtype: string
+      - name: last_modified
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 254050
+  - config_name: other
+    features:
+      - name: key
+        dtype: string
+      - name: type_name
+        dtype: string
+      - name: json_data
+        dtype: string
+      - name: revision
+        dtype: int32
+      - name: last_modified
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 94416
+  - config_name: covers_metadata
+    features:
+      - name: id
+        dtype: int64
+      - name: width
+        dtype: int32
+      - name: height
+        dtype: int32
+      - name: created
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 14775164
+  - config_name: wikidata
+    features:
+      - name: wikidata_id
+        dtype: string
+      - name: json_data
+        dtype: string
+    splits:
+      - name: train
+        num_examples: 166311
+---
+
+# Open Library
+
+> The world's catalog of books, converted to Parquet for training and analysis
+
+## What is it?
+
+**Open Library** is a complete snapshot of the [Open Library](https://openlibrary.org/) database — a project of the [Internet Archive](https://archive.org) that aims to create "one web page for every book ever published." The catalog contains bibliographic records for millions of authors, works, and editions, plus user-contributed ratings and reading logs.
+
+This dataset converts the official [OpenLibrary Data Dumps](https://openlibrary.org/developers/dumps) from their native TSV+JSON format into clean, columnar Apache Parquet files with Zstd compression. Every field from every record type is preserved — nothing is dropped.
+
+**Dump date:** 2026-02 | **Total records:** 144.5M | **License:** [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/) (Public Domain)
+
+## What is being released?
+
+The dataset contains **11 configs**, one per entity type. Each config has one or more Parquet shards (~1M rows each):
+
+```
+data/
+  authors/
+  works/
+  editions/
+  ratings/
+  reading-log/
+  redirects/
+  deletes/
+  lists/
+  other/
+  covers_metadata/
+  wikidata/
+```
+
+| Config | Records | Description |
+|--------|---------|-------------|
+| `authors` | 15.1M | Authors with biographies, birth/death dates, and cross-references to Wikidata/VIAF/ISNI |
+| `works` | 40.7M | Abstract works linking editions together, with subjects and descriptions |
+| `editions` | 55.6M | Physical editions with ISBNs, publishers, page counts, languages, and cover IDs |
+| `ratings` | 599.8K | User star ratings (1-5) for works and editions |
+| `reading-log` | 11.8M | User reading shelves: want-to-read, currently-reading, already-read |
+| `redirects` | 1.7M | Key redirects (merged or moved records) |
+| `deletes` | 3.7M | Deleted record stubs |
+| `lists` | 254.1K | User-created reading lists with seed references |
+| `other` | 94.4K | Miscellaneous types: languages, i18n strings, templates, macros |
+| `covers_metadata` | 14.8M | Cover image dimensions (width, height) for cover IDs |
+| `wikidata` | 166.3K | Wikidata cross-reference records with full JSON |
+
+## How to download and use
+
+### Using `datasets`
+
+```python
+from datasets import load_dataset
+
+# Load a specific config
+authors = load_dataset("open-index/open-library", "authors", split="train")
+editions = load_dataset("open-index/open-library", "editions", split="train")
+
+# Stream for large configs
+works = load_dataset("open-index/open-library", "works", split="train", streaming=True)
+for doc in works:
+    print(doc["key"], doc["title"])
+```
+
+### Using `huggingface_hub`
+
+```python
+from huggingface_hub import snapshot_download
+
+folder = snapshot_download(
+    "open-index/open-library",
+    repo_type="dataset",
+    local_dir="./open-library/",
+    allow_patterns="data/authors/*",  # download one config
+)
+```
+
+For faster downloads, install `pip install huggingface_hub[hf_transfer]` and set `HF_HUB_ENABLE_HF_TRANSFER=1`.
+
+### Using DuckDB
+
+```sql
+-- Find all editions of a work
+SELECT key, title, isbn_13, publishers, publish_date
+FROM read_parquet('hf://datasets/open-index/open-library/data/editions/*.parquet')
+WHERE work_keys LIKE '%OL45804W%'
+LIMIT 20;
+
+-- Top-rated works
+SELECT work_key, avg(rating) AS avg_rating, count(*) AS num_ratings
+FROM read_parquet('hf://datasets/open-index/open-library/data/ratings/*.parquet')
+GROUP BY work_key
+HAVING count(*) >= 100
+ORDER BY avg_rating DESC
+LIMIT 10;
+
+-- Authors with Wikidata links
+SELECT key, name, wikidata_id, birth_date, death_date
+FROM read_parquet('hf://datasets/open-index/open-library/data/authors/*.parquet')
+WHERE wikidata_id IS NOT NULL
+LIMIT 10;
+```
+
+# Dataset card for Open Library
+
+## Dataset Description
+
+- **Homepage:** [https://openlibrary.org](https://openlibrary.org)
+- **Source Dumps:** [https://openlibrary.org/developers/dumps](https://openlibrary.org/developers/dumps)
+- **Repository:** [https://huggingface.co/datasets/open-index/open-library](https://huggingface.co/datasets/open-index/open-library)
+- **Point of Contact:** Please create a discussion on the Community tab
+- **License:** CC0 1.0 Universal (Public Domain)
+
+## Dataset Structure
+
+### Authors
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `key` | string | OpenLibrary key, e.g. `/authors/OL1A` |
+| `name` | string | Display name |
+| `alternate_names` | string | JSON array of alternative name forms |
+| `bio` | string | Biography text (unwrapped from text_block) |
+| `birth_date` | string | Free-form birth date |
+| `death_date` | string | Free-form death date |
+| `date` | string | General date string |
+| `entity_type` | string | `"person"`, `"org"`, or `"event"` |
+| `fuller_name` | string | Full legal name |
+| `personal_name` | string | Personal name variant |
+| `title` | string | Honorific (e.g. "Sir", "OBE") |
+| `photos` | string | JSON array of cover image IDs |
+| `links` | string | JSON array of external link objects |
+| `remote_ids` | string | JSON object: `wikidata`, `viaf`, `isni`, `goodreads`, etc. |
+| `wikidata_id` | string | Extracted from `remote_ids.wikidata` |
+| `viaf_id` | string | Extracted from `remote_ids.viaf` |
+| `isni` | string | Extracted from `remote_ids.isni` |
+| `source_records` | string | JSON array of import source identifiers |
+| `revision` | int32 | Record revision number |
+| `created` | string | ISO 8601 creation timestamp |
+| `last_modified` | string | ISO 8601 last modification timestamp |
+
+### Works
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `key` | string | OpenLibrary key, e.g. `/works/OL45804W` |
+| `title` | string | Work title |
+| `subtitle` | string | Subtitle |
+| `author_keys` | string | JSON array of author keys, e.g. `["/authors/OL1A"]` |
+| `covers` | string | JSON array of cover image IDs |
+| `description` | string | Work description (unwrapped from text_block) |
+| `notes` | string | Editorial notes |
+| `subjects` | string | JSON array of subject headings |
+| `subject_places` | string | JSON array of geographic subjects |
+| `subject_people` | string | JSON array of people subjects |
+| `subject_times` | string | JSON array of time period subjects |
+| `lc_classifications` | string | JSON array of Library of Congress classification numbers |
+| `first_publish_date` | string | Earliest known publication date |
+| `revision` | int32 | Record revision number |
+| `created` | string | ISO 8601 creation timestamp |
+| `last_modified` | string | ISO 8601 last modification timestamp |
+
+### Editions
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `key` | string | OpenLibrary key, e.g. `/books/OL1M` |
+| `title` | string | Edition title |
+| `subtitle` | string | Subtitle |
+| `author_keys` | string | JSON array of author keys |
+| `work_keys` | string | JSON array of parent work keys |
+| `isbn_10` | string | JSON array of ISBN-10 numbers |
+| `isbn_13` | string | JSON array of ISBN-13 numbers |
+| `lccn` | string | JSON array of Library of Congress Control Numbers |
+| `oclc_numbers` | string | JSON array of OCLC/WorldCat IDs |
+| `ocaid` | string | Internet Archive identifier |
+| `identifiers` | string | JSON object: `goodreads`, `librarything`, `amazon`, etc. |
+| `local_id` | string | JSON array of local URNs |
+| `publishers` | string | JSON array of publisher names |
+| `publish_date` | string | Publication date (free-form) |
+| `publish_places` | string | JSON array of publication places |
+| `publish_country` | string | MARC21 country code |
+| `edition_name` | string | Edition descriptor (e.g. "1st ed.") |
+| `by_statement` | string | Authorship statement |
+| `contributions` | string | JSON array of contributors |
+| `languages` | string | JSON array of MARC language codes, e.g. `["eng"]` |
+| `translated_from` | string | JSON array of original language codes |
+| `translation_of` | string | Original title if translated |
+| `number_of_pages` | int32 | Page count |
+| `pagination` | string | Pagination description |
+| `physical_format` | string | "Paperback", "Hardcover", etc. |
+| `physical_dimensions` | string | Dimensions string |
+| `weight` | string | Weight string |
+| `covers` | string | JSON array of cover image IDs |
+| `description` | string | Edition description |
+| `first_sentence` | string | Opening sentence |
+| `notes` | string | Editorial notes |
+| `table_of_contents` | string | JSON array of TOC entries |
+| `subjects` | string | JSON array of subject headings |
+| `dewey_decimal_class` | string | JSON array of Dewey Decimal numbers |
+| `lc_classifications` | string | JSON array of LC classification numbers |
+| `genres` | string | JSON array of genre labels |
+| `series` | string | JSON array of series names |
+| `links` | string | JSON array of external links |
+| `source_records` | string | JSON array of import sources |
+| `copyright_date` | string | Copyright year |
+| `other_titles` | string | JSON array of alternative titles |
+| `work_titles` | string | JSON array of related work titles |
+| `classifications` | string | JSON object of additional classification schemes |
+| `revision` | int32 | Record revision number |
+| `created` | string | ISO 8601 creation timestamp |
+| `last_modified` | string | ISO 8601 last modification timestamp |
+
+### Ratings
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `work_key` | string | Work reference, e.g. `/works/OL123W` |
+| `edition_key` | string | Edition reference (optional) |
+| `rating` | int32 | Star rating, 1-5 |
+| `date` | string | Date the rating was submitted |
+
+### Reading Log
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `work_key` | string | Work reference |
+| `edition_key` | string | Edition reference (optional) |
+| `shelf` | string | One of: `want-to-read`, `currently-reading`, `already-read` |
+| `date` | string | Date of the shelf action |
+
+### Redirects
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `key` | string | Old/redirected key |
+| `location` | string | Target key being redirected to |
+| `type_name` | string | Type key (e.g. `/type/redirect`) |
+| `revision` | int32 | Record revision number |
+| `last_modified` | string | ISO 8601 timestamp |
+
+### Deletes
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `key` | string | Deleted record key |
+| `type_name` | string | Type key (e.g. `/type/delete`) |
+| `revision` | int32 | Record revision number |
+| `last_modified` | string | ISO 8601 timestamp |
+
+### Lists
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `key` | string | List key |
+| `name` | string | List name |
+| `description` | string | List description |
+| `seeds` | string | JSON array of seed references |
+| `seed_count` | int32 | Number of seeds in the list |
+| `revision` | int32 | Record revision number |
+| `created` | string | ISO 8601 creation timestamp |
+| `last_modified` | string | ISO 8601 timestamp |
+
+### Covers Metadata
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `id` | int64 | Cover image ID |
+| `width` | int32 | Image width in pixels |
+| `height` | int32 | Image height in pixels |
+| `created` | string | Upload timestamp |
+
+### Wikidata
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `wikidata_id` | string | Wikidata Q-identifier |
+| `json_data` | string | Full JSON body of the Wikidata record |
+
+### Other
+
+| Column | Type | Description |
+|--------|------|-------------|
+| `key` | string | Record key |
+| `type_name` | string | Type key |
+| `json_data` | string | Full JSON body |
+| `revision` | int32 | Record revision number |
+| `last_modified` | string | ISO 8601 timestamp |
+
+## Dataset Creation
+
+### Source Data
+
+[Open Library](https://openlibrary.org/) is an open, editable library catalog maintained by the [Internet Archive](https://archive.org). It publishes monthly bulk data dumps at [openlibrary.org/developers/dumps](https://openlibrary.org/developers/dumps) covering every record in the database: authors, works, editions, ratings, reading logs, redirects, deleted records, user lists, cover metadata, and Wikidata cross-references.
+
+### Data Processing
+
+The processing pipeline converts each dump type from its native format into clean Parquet:
+
+1. **Download** the `.txt.gz` dump from Internet Archive (the `_latest` URLs redirect to the most recent monthly snapshot)
+2. **Stream** through the gzipped file line-by-line — no intermediate uncompressed copy
+3. **Parse** each TSV line and extract all JSON fields using [gjson](https://github.com/tidwall/gjson) (zero-allocation field extraction)
+4. **Normalize** nested structures: text blocks (`{"type":"/type/text","value":"..."}`) are unwrapped to plain strings; language references (`[{"key":"/languages/eng"}]`) become `["eng"]`; author role arrays become flat key lists
+5. **Write** to sharded Parquet files with Zstd compression (~1M rows per shard, 500K rows per row group)
+
+The full pipeline processes all 11 dump types without storing any intermediate files. Memory usage stays constant regardless of dump size because the pipeline is fully streaming.
+
+## Considerations for Using the Data
+
+### Field Encoding
+
+Array and object fields (e.g. `subjects`, `identifiers`, `remote_ids`) are stored as **JSON strings**, not native Parquet lists or maps. This maximizes flexibility — you can query them with DuckDB's `json_extract()` or parse them in Python with `json.loads()`. Frequently-used identifiers (`wikidata_id`, `viaf_id`, `isni`) are also extracted as top-level columns for convenience.
+
+### Data Quality
+
+Open Library is a community-edited catalog. Some records have inconsistent formatting, missing fields, or duplicate entries. Dates are free-form strings (e.g. "1899", "March 1980", "c. 1650"). The `redirects` config can help resolve merged/moved records.
+
+### Personal Information
+
+Author records contain biographical information (names, birth/death dates, biographies) sourced from public library catalogs. Reading logs and ratings are anonymized — they contain no user identifiers.
+
+## Additional Information
+
+### Licensing
+
+Open Library data is released under [CC0 1.0](https://creativecommons.org/publicdomain/zero/1.0/) (Public Domain). You are free to use it for any purpose without attribution, though attribution to Open Library and the Internet Archive is appreciated.
+
+### Contact
+
+Please open a discussion on the [Community tab](https://huggingface.co/datasets/open-index/open-library/discussions) for questions, feedback, or issues.