# orca.keyed

> A module of Orca's API.

Keyed partitions: keys that are names, read from a column of a dataset.

```mojo
from orca.keyed import Keyed

comptime Labels = Pipeline[
    "labels", Label, Score, partitions=Keyed["av2.logs", "log_id"], keys_per_run=100
]
```

The keys are the distinct values of `column` in the current snapshot of the
warehouse dataset `dataset` (`ORCA_WAREHOUSE`), each a `Name`. They live in
data rather than in the source because there can be thousands and they
grow. `--partitions` takes a list of names, `@all` for every current key,
or `@file:<path>` for a list one per line; a range is refused, and so is a
name the dataset doesn't have, so a typo doesn't make a run of nothing.
`<binary> keys` prints the snapshot and the keys, for the scheduler, which
links no iceberg.

A keyed pipeline has no calendar, so `schedule=` and `fills=` don't compile
with one (`Pipeline.check`). This module imports iceberg, so only binaries
with a keyed pipeline build it.

## Structs

### `Keyed`

```mojo
struct Keyed[dataset_: StringSpan[ImmStaticOrigin], column_: StringSpan[ImmStaticOrigin]]
```

A partition per distinct value of `column_` in the dataset `dataset_` (`namespace.table`).

Implements: `Movable`, `Partitions`

#### `K`

```mojo
comptime K = Name
```

#### `kind`

```mojo
def kind() -> StaticString
```

#### `start`

```mojo
def start() -> StaticString
```

#### `dataset`

```mojo
def dataset() -> StaticString
```

#### `column`

```mojo
def column() -> StaticString
```

#### `parse`

```mojo
def parse(s: StringSpan, check: Bool) -> List[Name]
```

#### `fill`

```mojo
def fill(year: Int, month: Int, day: Int, previous: Bool) -> Name
```

#### `keys`

```mojo
def keys() -> Tuple[Int64, List[String]]
```