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+# Wikidata Extraction
+
+This dataset contains all RDF triples extracted from the latest Wikidata, converted from the N-Triples format to Parquet.
+
+The data originates from [Wikidata](https://www.wikidata.org/), a free and open knowledge base that acts as central storage for structured data used by Wikipedia and other Wikimedia projects. The source file is the "truthy" N-Triples dump (`latest-truthy.nt.bz2`), which contains only the current, non-deprecated statements.
+
+The code to extract this data is available at [github.com/piebro/wikidata-extraction](https://github.com/piebro/wikidata-extraction).
+
+## Schema
+
+Each row represents a single RDF triple with four columns:
+
+| Column      | Type   | Description                                                        |
+|-------------|--------|--------------------------------------------------------------------|
+| `subject`   | string | The entity being described (typically a Wikidata Q-ID URL)         |
+| `predicate` | string | The property or relationship (typically a Wikidata P-ID URL)       |
+| `object`    | string | The value, which can be another entity, literal, or external ID    |
+| `language`  | string | Language tag for literals (e.g., "en", "de"), null otherwise       |
+
+### Example Values
+
+```
+subject:   http://www.wikidata.org/entity/Q42
+predicate: http://www.w3.org/2000/01/rdf-schema#label
+object:    Douglas Adams
+language:  en
+```
+
+This triple means: "Q42 (Douglas Adams) has the English label 'Douglas Adams'".
+
+```
+subject:   http://www.wikidata.org/entity/Q42
+predicate: http://www.wikidata.org/prop/direct/P31
+object:    http://www.wikidata.org/entity/Q5
+language:  null
+```
+
+This triple means: "Q42 (Douglas Adams) is an instance of (P31) Q5 (human)". The language is null because the object is a URI, not a language-tagged literal.
+
+## Data Organization
+
+### Triplets
+
+The `triplets/` folder contains the raw RDF triples partitioned into Parquet files (`triplets/*.parquet`).
+
+### Extractions
+
+The `extractions/` folder contains extracted lookup tables and themed datasets:
+
+| File | Description |
+|------|-------------|
+| `entity_labels.parquet` | Maps entities to their labels |
+| `predicate_labels.parquet` | Maps predicates to their labels and descriptions |
+| `music/spotify_artist.parquet` | Spotify artist data |
+| `music/spotify_album.parquet` | Spotify album data |
+| `music/spotify_track.parquet` | Spotify track data |
+| `video/youtube_channel.parquet` | YouTube channel data |
+| `video/youtube_video.parquet` | YouTube video data |
+| `video/letterboxd_film.parquet` | Letterboxd film data |
+| `social/bluesky.parquet` | Bluesky account data |
+| `social/subreddit.parquet` | Subreddit data |
+| `social/patreon.parquet` | Patreon creator data |
+| `book/goodread_book.parquet` | Goodreads book data |
+| `book/gutenberg_book.parquet` | Project Gutenberg book data |
+| `other/github.parquet` | GitHub repository data |
+| `other/website.parquet` | Website data |
+| `other/non_profit_organization.parquet` | Non-profit organization data |
+
+## Usage
+
+Query the dataset using any Parquet-compatible tool (DuckDB, Pandas, Polars, etc.):
+
+### Find All Properties of an Entity
+
+```python
+import duckdb
+
+df = duckdb.sql("""
+    SELECT *
+    FROM 'triplets/*.parquet'
+    WHERE subject = 'http://www.wikidata.org/entity/Q42'
+""").df()
+print(df)
+```
+
+### Look Up Entity Labels
+
+```python
+import duckdb
+
+entity_ids = ["Q42", "Q5", "Q64"]
+entity_uris = [f"http://www.wikidata.org/entity/{e}" for e in entity_ids]
+
+df = duckdb.sql(f"""
+    SELECT entity, label
+    FROM 'extractions/entity_labels.parquet'
+    WHERE entity IN {tuple(entity_uris)}
+""").df()
+print(df)
+```
+
+## License
+
+Wikidata content is available under [CC0 1.0 Universal](https://creativecommons.org/publicdomain/zero/1.0/).