clickhouse-arp.yaml

metadata:
  # Manually Configured Metadata Section.
  name: CLICKHOUSE
  apiname: clickhouse
  spec_version: '1'

syntax:
  # Manually Configured Syntax Section.
  identifier_quote: '"'
  identifier_length_limit: 128
  allows_boolean_literal: false
  map_boolean_literal_to_bit: false
  supports_catalogs: false
  supports_schemas: true

data_types:
  mappings:
  # Manually Configured Data Types Mappings Section.
  - source:
      name: "INTEGER"
    dremio:
      name: "integer"
    required_cast_arguments: "none"
  - source:
      name: "REAL"
    dremio:
      name: "double"
    required_cast_arguments: "none"
  - source:
      name: "VARCHAR"
    dremio:
      name: "varchar"
    required_cast_arguments: "none"
  - source:
      name: "STRING"
    dremio:
      name: "varchar"
    required_cast_arguments: "none"
  - source:
      name: "DATE"
    dremio:
      name: "varchar"
    required_cast_arguments: "none"
  - source:
      name: "DATETIME"
    dremio:
      name: "timestamp"
    required_cast_arguments: "none"
  - source:
      name: "TIMESTAMP"
    dremio:
      name: "timestamp"
    required_cast_arguments: "none"

relational_algebra:
  aggregation:
    enable: true
    group_by_ordinal: false
    distinct: true
    count_functions:
      count_star:
        enable: true
      count:
        enable: true
      count_distinct:
        enable: true
    functions:
    - names:
      - "avg"
      signatures:
      - args:
        - "double"
        return: "double"
      - args:
        - "integer"
        return: "double"
    - names:
      - "max"
      - "min"
      signatures:
      - args:
        - "integer"
        return: "integer"
      - args:
        - "double"
        return: "double"
      - args:
        - "varchar"
        return: "varchar"
    - names:
      - "sum"
      signatures:
      - args:
        - "double"
        return: "double"
      - args:
        - "integer"
        return: "bigint"

  except:
    enable: false
  project:
    enable: true
  join:
    enable: true
    cross:
      enable: true
    inner:
      enable: true
      inequality: true
    left:
      enable: true
      inequality: true
    right:
      enable: false
      inequality: false
    full:
      enable: false
      inequality: false
  sort:
    enable: true
    order_by:
      enable: true
      default_nulls_ordering: high
    fetch_offset:
      offset_fetch:
        enable: true
        format: 'LIMIT {1} OFFSET {0}'
      offset_only:
        enable: false
      fetch_only:
        enable: true
        format: 'LIMIT {0}'
  union:
    enable: false
  union_all:
    enable: false
  values:
    enable: false
    method: values

# Describe the set of function signatures that are internally supported.
expressions:
  subqueries:
    correlated: true
    scalar: true
    in_clause: true
  supports_case: true
  supports_over: false
  operators:
    - names:
      - "="
      - "!="
      - "<>"
      - ">"
      - ">="
      - "<"
      - "<="
      signatures:
      - args:
        - "double"
        - "double"
        return: "boolean"
      - args:
        - "double"
        - "integer"
        return: "boolean"
      - args:
        - "double"
        - "varchar"
        return: "boolean"
      - args:
        - "integer"
        - "double"
        return: "boolean"
      - args:
        - "integer"
        - "integer"
        return: "boolean"
      - args:
        - "integer"
        - "varchar"
        return: "boolean"
      - args:
        - "varchar"
        - "varchar"
        return: "boolean"
    - names:
      - "not"
      signatures:
      - args:
        - "boolean"
        return: "boolean"
    # Example scalar function
    - names:
      - "sign"
      signatures:
      - args:
        - "double"
        return: "double"
      - args:
        - "integer"
        return: "integer"
        # Example rewrite (although this is not necessary here as the default is the same)
        rewrite: "SIGN({0})"

  variable_length_operators:
    - names:
        - and
      variable_signatures:
        - return: boolean
          arg_type: boolean
    - names:
        - or
      variable_signatures:
        - return: boolean
          arg_type: boolean