docs/paimon-integration.md

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# Paimon Integration

The standalone library is intentionally independent of Paimon core. Paimon
integration should be a thin adapter:

- Pass the query DSL as a JSON string to the standalone reader.
- Implement a Paimon `GlobalIndexerFactory` that delegates to Java
  `FullTextIndexWriter` and `FullTextIndexReader`.
- Pass serialized 64-bit Roaring row-id filters to reader search when another
  index or predicate pushdown has already produced an allowed candidate set.
- Store produced files as global index files.

Suggested index identifier:

```text
fulltext
```

Suggested option namespace:

```text
fulltext.tokenizer
fulltext.text-fields
fulltext.ngram.min-gram
fulltext.ngram.max-gram
fulltext.ngram.prefix-only
fulltext.jieba.search-mode
fulltext.jieba.ordinal-position
fulltext.lower-case
fulltext.max-token-length
fulltext.ascii-folding
fulltext.stem
fulltext.language
fulltext.remove-stop-words
fulltext.stop-words
fulltext.with-position
```

The standalone library accepts both unprefixed keys and `fulltext.` prefixed
keys.

Query JSON supports `match`, `multi_match`, `match_phrase`, `boolean`, and
boost-demotion queries. `match` accepts `fuzziness`, `max_expansions`, and
`prefix_length`; use `fuzziness: "auto"` for automatic edit distance. If
`match.column` is omitted, the native reader searches every text field
configured in the index, so Paimon can derive native text fields from its
extra-fields mechanism without adding a user-facing `multi_match` requirement.