> ## Documentation Index
> Fetch the complete documentation index at: https://docs.woodwide.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Per-Column Profile Stats

> Per-column profile (null %, approx distinct, min/max/mean, histograms) for the dataset's current ready version. Computed lazily from the curated Parquet on first request and cached on the version thereafter.



## OpenAPI

````yaml /openapi.json get /datasets/{dataset_id}/column-stats
openapi: 3.1.0
info:
  title: Woodwide API
  description: API service for the Woodwide platform
  version: 0.1.0
servers:
  - url: https://api.woodwide.ai
    description: Production
security: []
paths:
  /datasets/{dataset_id}/column-stats:
    get:
      tags:
        - Datasets
      summary: Per-Column Profile Stats
      description: >-
        Per-column profile (null %, approx distinct, min/max/mean, histograms)
        for the dataset's current ready version. Computed lazily from the
        curated Parquet on first request and cached on the version thereafter.
      operationId: dataset_column_stats_datasets__dataset_id__column_stats_get
      parameters:
        - name: dataset_id
          in: path
          required: true
          schema:
            type: string
            title: Dataset Id
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DatasetColumnStatsResponse'
        '422':
          description: Validation Error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/HTTPValidationError'
      security:
        - HTTPBearer: []
components:
  schemas:
    DatasetColumnStatsResponse:
      properties:
        row_count:
          anyOf:
            - type: integer
            - type: 'null'
          title: Row Count
          description: Row count of the current version.
        columns:
          items:
            $ref: '#/components/schemas/DatasetColumnProfile'
          type: array
          title: Columns
          description: Per-column stats in the stored schema's column order.
      type: object
      required:
        - columns
      title: DatasetColumnStatsResponse
      description: |-
        Per-column profile for the dataset's current ready version.

        Computed lazily from the materialized Parquet on first request and
        cached on the version thereafter. ``columns`` is empty when profiling
        fails (e.g. the Parquet is unreachable) — the UI degrades gracefully.
    HTTPValidationError:
      properties:
        detail:
          items:
            $ref: '#/components/schemas/ValidationError'
          type: array
          title: Detail
      type: object
      title: HTTPValidationError
    DatasetColumnProfile:
      properties:
        name:
          type: string
          title: Name
        dtype:
          anyOf:
            - type: string
            - type: 'null'
          title: Dtype
          description: Physical (Arrow) column type.
        null_pct:
          anyOf:
            - type: number
            - type: 'null'
          title: Null Pct
          description: Percent of null values, rounded to 1 decimal.
        distinct:
          anyOf:
            - type: integer
            - type: 'null'
          title: Distinct
          description: Approximate distinct count.
        min:
          anyOf:
            - type: string
            - type: 'null'
          title: Min
          description: Minimum value, formatted as a string.
        max:
          anyOf:
            - type: string
            - type: 'null'
          title: Max
          description: Maximum value, formatted as a string.
        mean:
          anyOf:
            - type: number
            - type: 'null'
          title: Mean
          description: Mean — numeric columns only.
        bins:
          anyOf:
            - items:
                type: integer
              type: array
            - type: 'null'
          title: Bins
          description: >-
            8-bin equi-width histogram counts between min and max. Null for
            non-numeric, constant, or all-null columns.
      type: object
      required:
        - name
      title: DatasetColumnProfile
      description: Lazily computed profile stats for one column.
    ValidationError:
      properties:
        loc:
          items:
            anyOf:
              - type: string
              - type: integer
          type: array
          title: Location
        msg:
          type: string
          title: Message
        type:
          type: string
          title: Error Type
        input:
          title: Input
        ctx:
          type: object
          title: Context
      type: object
      required:
        - loc
        - msg
        - type
      title: ValidationError
  securitySchemes:
    HTTPBearer:
      type: http
      scheme: bearer

````