# SQLite inspection mirror

`sphragis.sqlite` mirrors every row and column of all four canonical Parquet
configurations. It is intended for convenient local inspection; Parquet remains
the canonical benchmark representation.

Each configuration is a table named after the configuration, for example
`sentence_10`. List-valued Parquet columns are stored as compact JSON
text. `_split_row_index` records the original physical row order within each
split. `_mirror_manifest` records row counts, column lists, and content hashes.

The top-level `text` column is a JSON list: one string for atomic rows and one
string per constituent sentence or line for fixed-size chunks. For example,
retrieve the ten separate sentences in the first validation row as follows:

```sh
sqlite3 -readonly -line inspection/sphragis.sqlite \
  "SELECT key AS sentence_index, value AS sentence
   FROM json_each((
     SELECT text FROM sentence_10
     WHERE split = 'validation'
     ORDER BY _split_row_index LIMIT 1
   ));"
```

The top-level `conllu` column is also a JSON list with one CoNLL-U document per
corresponding `text` unit. SQLite's `json_each()` can inspect these documents in
the same way.

List the available tables with:

```sh
sqlite3 -readonly inspection/sphragis.sqlite ".tables"
```

Regenerate and validate the mirror from the Parquet files with:

```sh
python scripts/build_sqlite_mirror.py
python scripts/build_sqlite_mirror.py --check
```