# Ported data plane

One includes a bounded, ported data plane: its own recording format, a columnar
chunk model, chunk store and index, query and dataframe, entity database,
transforms, analytics, video, catalog, catalog wire, tile addressing, and one
importer for an external recording format. These are One-owned Data atoms with
their own contracts and tests. They are not a second authoring surface, and they
do not turn Arrow or any external format into One semantics.

## Internal record formats, not authored surfaces

One's recording formats are internal record formats. They are produced and
consumed by owning Data atoms; they are not `.one` syntax and are not something
an application authors directly.

- `ONE1` is a single-chunk frame: a magic value, a version, the entity-path
  length, the entity-path bytes, and an Arrow IPC stream.
- `ONER` is a recording:

```text
ONER = RECORDING_MAGIC
     | version            (u32 little-endian)
     | chunk_count        (u32 little-endian)
     | repeated [ length   (u32 little-endian)
                | chunk frame ]
```

- `ONEB` is a `StoreBundle` blob: recordings plus an optional blueprint, with a
  per-recording revision.

Each reader bounds its inputs and rejects bad magic, unsupported version,
truncation, and trailing bytes rather than accepting a partial or over-long
record. Arrow is used directly as the columnar chunk layout inside these
One-owned atoms. A columnar representation provider seam is introduced only when
a second real columnar realization exists.

## Columnar chunks and storage

The columnar atoms are:

- `one-chunk` — one entity path, timelines, and typed component columns, with
  latest-at and range access;
- `one-chunk-store` — `latest_at`, range, `row_time`, `timeline_rows`,
  `ordered_rows`, atomic `one-log-message` ingestion, `optimize`, `apply_lens`,
  and a deterministic revision;
- `one-chunk-index` — the index over stored chunks; and
- `one-columnar-schema` — the physical column schema shared by the atoms above.

## Query, dataframe, and entities

The query and entity atoms are `one-query`, `one-dataframe` (`QueryPlan`,
`Table`, `AggregateFn`), `one-analytical-query`, and `one-entity-db`. `EntityDb`
exposes table, latest table, `query_latest`, aggregates, `window_aggregate`,
`group_aggregate`, `analytical_query`, manifest, and ingest. `one-transform`
owns transforms, and `one-entity` owns `EntityPath`. The experience-oriented
views described in [Experience and presentation](/one/model/experience) compose
these same atoms rather than re-owning entity or timeline meaning.

## Analytics, video, catalog, and tiles

- `one-analytics` — bounded time-bucket `aggregate` with `MAX_SCAN_ROWS` and
  `MAX_BUCKETS`, plus descriptive statistics. These statistics are descriptive
  data; they are never authority or evidence.
- `one-video` — `EncodedVideoFrame`, `VideoCodec`, decoded RGBA8 frames, and an
  injectable `VideoDecoder`. One owns the encoded-frame and decoder contract; no
  decoder runtime is owned here, and a concrete decoder remains a removable
  realization.
- `one-catalog` — `Catalog`, `EntryId`, `EntryName`, `Segment`, and
  `EntryKind::Dataset | Table`, all bounded. `one-adapter-catalog-wire` maps the
  catalog to a wire form of a 4-byte little-endian length plus canonical JSON,
  with an in-band fault. The wire adapter owns no HTTP, TLS, or authorization.
- `one-map-tiles` — an Experience atom with `TileCoord`, `MAX_ZOOM = 24`,
  `tiles_for_rect`, longitude and latitude conversions bounded to
  ±85.05112878 and ±180, `MAX_TILES = 4096`, and a bounded `TileFetcher`. The
  atom owns no network, cache, or authority; a network tile provider is a
  removable realization.

## Generated and imported material

`standard_telemetry_module_typescript` is deterministic generated TypeScript
source for the standard telemetry model. It is a projection, not a second model
and not a second semantic source.

`one-adapter-rrd` is a real importer for one external recording format. It parses
`RRF2` framing plus `log_msg.proto` messages over LZ4 and Arrow IPC and maps them
to `one-chunk`. It is not the One format and not an embedded external runtime.
`ImportedRecording::unsupported_components` reports every component the mapping
could not represent, so loss is explicit rather than silent.

The pure telemetry atoms build for `wasm32-unknown-unknown`, which activates the
browser execution profile's data layer. A browser renderer or product remains
inactive.

## Relationship to One Database

This ported data plane is not One Database. The native transactional, temporal,
and reactive database described in [One Database](/one/guides/one-database) is a
separate, still-deferred realization. Do not present a native SQL database as
available here, and do not present these bounded atoms as a general durable
transaction engine. The broader physical, storage, and movement model remains
owned by [Data and state](/one/model/data).

## Illustrative syntax is not a data format

An authored state declaration describes meaning; it does not describe `ONE1`,
`ONER`, columns, or Arrow layout. The `.one` syntax below is illustrative
end-product syntax and is not exercised by the ported data atoms:

```one
one 1

semantic acme.telemetry
    domain one.data@1

    state Telemetry@1
        stores EntitySamples
        retention 30d
```

The Rust API references on this page (crate and type names such as `one-chunk`,
`EntityDb`, and `TileCoord`) are demonstrated by their owning crates and tests.

Next: read [Data and state](/one/model/data) or
[One Database](/one/guides/one-database).

## Normative owner & evidence

The normative owner is
[systems/data/AGENTS.md](https://github.com/muijf/one/blob/main/systems/data/AGENTS.md).
Tile addressing is additionally owned by
[systems/experience/AGENTS.md](https://github.com/muijf/one/blob/main/systems/experience/AGENTS.md),
under the repository composition law in
[AGENTS.md](https://github.com/muijf/one/blob/main/AGENTS.md).

Demonstrated today: the `ONE1`/`ONER`/`ONEB` record formats and their rejection
bounds; the columnar chunk, store, index, schema, query, dataframe, entity, and
transform atoms; `one-analytics`; the `one-video` contract; `one-catalog` and its
wire adapter; `one-map-tiles`; the generated telemetry TypeScript module; and the
`one-adapter-rrd` importer with explicit unsupported components. Each is
exercised by its owning crate.

Illustrative or deferred: the `one.data@1` authoring snippet above, a native SQL
database, a concrete network tile or video provider, a browser renderer or
product, and any second columnar representation provider.