You are viewing documentation for Looker 25.10. Click this link to see the most recent documentation.

Field parameters

This page links to all of the LookML parameters that define fields.

There are several types of fields:

Dimensions represent a column in a table, or a computed value based on some sort of column manipulation or combination
Dimension Groups are only used with time-based data, and enable you to create many time-based dimensions at one time
Measures are similar to aggregate functions in SQL (for example, COUNT, SUM, AVG) and represent information about multiple rows
Filters create a filter-only field users can use to provide input to a templated filter or a conditional join
Parameters create a filter-only field users can use to provide input to a Liquid {% parameter %} tag

Example usage

Hold the pointer over a parameter name to see a quick description. Click a parameter name to jump to its reference page.

When a parameter can be set to one of several specific options, the default value is listed first.

## STRUCTURAL PARAMETERS
view: view_name {
  (dimension |dimension_group |measure |filter | parameter):field_name{
    intervals: [interval, interval, …]
    timeframes: [timeframe, timeframe, …]

    # ACTION AND LINKING PARAMETERS
    action: {
      label: "Label to Appear in Action Menu"
      url: "url"
      icon_url: "url"
      form_url: "url"
      param: {
        name:  "name string"
        value:  "value string"
      }
      # Possibly more param definitions
      form_param: {
        name:  "title"
        type: select | string | textarea
        label:  "desired label name"
        required:  yes | no
        default:  "value string"
        option: {
          name:  "name string"
          value:  "value string"
        }
        # Possibly more option definitions
      }
      # Possibly more form_param definitions
    }
    drill_fields: [field_or_set, field_or_set, ...]
    tags: ["string1", "string2", ...]
    link: {
      label: "desired label name;"
      url: "desired_url"
      icon_url: "url_of_an_image_file"
    }
    # Possibly more link definitions
    # DISPLAY PARAMETERS
    alias: [old_field_name, old_field_name, ...]
    alpha_sort: yes | no
    description: "description string"
    group_label:  "desired group label name"
    group_item_label:  "label to use under the group label in the field picker"
    hidden: yes | no
    label: "desired label name"
    label_from_parameter: parameter_name
    order_by_field: dimension_name | dimension_group_name | measure_name 
    style: classic | interval | integer | relational
    view_label: "desired label name"

    # FILTER PARAMETERS
    can_filter: yes | no
    case_sensitive: yes | no
    filters: [dimension: "filter expression", dimension: "filter expression", ...]
    skip_drill_filter: yes | no

    # FILTER SUGGESTION PARAMETERS
    allowed_value: {
      label: "desired label name"
      value: "looker filter expression"
    }
    # Possibly more allowed_value definitions
    bypass_suggest_restrictions: yes | no
    full_suggestions: yes | no
    suggest_dimension: dimension_name
    suggest_explore: explore_name
    suggest_persist_for: "N (seconds | minutes | hours)"
    suggestable: yes | no
    suggestions: ["suggestion string", "suggestion string", "…"]<

    # QUERY PARAMETERS
    allow_approximate_optimization: yes | no
    approximate: yes | no
    approximate_threshold: N
    convert_tz: yes | no
    datatype: epoch | timestamp | datetime | date | yyyymmdd
    fanout_on: repeated_record_name
    precision: N
    primary_key: yes | no
    required_access_grants: [access_grant_name, access_grant_name, ...]
    required_fields: [field_name, field_name, ...]
    sql_distinct_key: SQL expression to define repeated entities ;;

    # VALUE AND FORMATTING PARAMETERS
    case: {
      when: {
        sql: SQL condition ;;
        label: "value"
      }
      # Possibly more when statements
    }
    default_value: "desired default value"
    direction: "row | column"
    end_location_field: dimension_name
    html: HTML expression using Liquid template elements ;;
    list_field: dimension_name

    percentile: Nth percentile
    sql: SQL expression to generate the field value ;;
    sql_end: SQL expression indicating the end time of a duration ;;
    sql_latitude: SQL expression to generate a latitude ;;
    sql_longitude: SQL expression to generate a longitude ;;
    sql_start: SQL expression indicating the start time of a duration ;;
    start_location_field: dimension_name
    tiers: [N, N, ...]
    type: dimension_field_type # For a dimension field
    type: dimension_group_type
# For a dimension_group field
    type: measure_field_type   # For a measure field
    type: filter_field_type    # For a filter field
    type: parameter_field_type # For a parameter field
    string_datatype: unicode # For a dimension field
    units: feet | kilometers | meters | miles | nautical_miles | yards
    value_format: "excel-style formatting string"
    value_format_name: format_name

    # VISUALIZATION PARAMETERS
    allow_fill: yes | no
    map_layer_name: name_of_map_layer
  }
}

Parameter definitions

D = Dimension
DG = Dimension Group
M = Measure
F = Filter
P = Parameter

Parameter Name	Valid Field Types	Description
Structural Parameters
`dimension`	D	Creates a dimension field
`dimension_group`	DG	Creates several time-based dimensions at the same time
`filter`	F	Creates a filter-only field for use in a templated filter or conditional join
`measure`	M	Creates a measure field
`parameter`	P	Creates a filter-only field users can use to provide input to a Liquid `{% parameter %}` tag
`intervals`	DG	Defines the set of duration dimensions you want in a `dimension_group` of `type: duration`
`timeframes`	DG	Defines the set of timeframe dimensions you want in a `dimension_group` of `type: time`
Action and Linking Parameters
`action`	D M	Creates a data action on a field that lets users perform tasks in other tools, directly from Looker
`drill_fields`	D DG M	Declares the list of fields that will be displayed when the measure or dimension is drilled into
`link`	D M	Creates links to other Looker and external content
`tags`	D DG M F P	Adds text that can be passed to other applications to provide data about a field
Display Parameters
`alias`	D DG M F P	Allows saved URLs with old field names to remain functional after a field is renamed
`alpha_sort`	D	Makes a `case` parameter sort its conditions alphabetically
`description`	D DG M F P	Adds a description to the field users can see when hovering the cursor over the field.
`group_label`	D DG M F	Groups fields together within a view in the field picker
`group_item_label`	D DG M F	Specifies a label to use for the field under its group label in the field picker
`hidden`	D DG M F P	Hides a field from the Explore UI
`label`	D DG M F P	Changes the way a field name appears in the field picker
`label_from_parameter`	D M	Changes the way a field name appears in a visualization based on the input to a `parameter`
`order_by_field`	D DG M	Sorts a field by the values of another field Supported for dimensions, dimension groups Supported for measures
`style`	D	Changes the way that tiers appear in the Looker UI for a dimension of `type: tier`
`view_label`	D DG M F P	Changes the fields that appear within a view in the field picker
Filter Parameters
`can_filter`	D DG M	Determines if a dimension or measure can be used as a filter
`case_sensitive`	D F	Determines if filters are case-sensitive for a dimension
`filter`	F	Creates a filter-only field for use in a templated filter
`filters`	M	Restricts a measure's calculation based on dimension limitations
`skip_drill_filter`	D	Stops a dimension from being added to the filters when a measure is drilled into
Filter Suggestion Parameters
`allowed_value`	P	Specifies the choices for a `parameter`
`bypass_suggest_restrictions`	D DG F P	Shows suggestions to users when `sql_always_where` is in use, but don't apply those limits to the suggestions
`full_suggestions`	D DG F P	Controls how Looker queries your database to provide suggestions for a field's values in the filter of an Explore. Looker can use a basic `SELECT DISTINCT` query, or Looker can use the full logic of the Explore, including joins and `sql_always_where` and `access_filter` parameters.
`suggest_dimension`	D DG M F P	Bases the suggestions for a field on the values of a different dimension
`suggest_explore`	D DG M F P	Bases the suggestions for a field on the values of a different Explore
`suggest_persist_for`	D F P	Changes the cache settings for Looker filter suggestions
`suggestable`	D DG M F P	Enables or disables suggestions for a field
`suggestions`	D F P	Declares a list of values that will be used for a field's suggestions
Query Parameters
`allow_approximate_optimization`	M	Allows distinct count approximations for measures of `type: count` or `type: count_distinct`, so that the measure can be used for aggregate awareness
`approximate`	M	Performs an approximate count for a measure of `type: count_distinct`. See the `approximate` documentation page for a list of dialects that support this parameter.
`approximate_threshold`	M	Sets the count at which BigQuery switches from an exact count distinct to an approximate count distinct
`convert_tz`	D DG M F P	Disables automatic time zone conversion for a field
`datatype`	D DG F M	Specifies the type of time data you are providing to a field
`fanout_on`	D DG M	Enables access to Google BigQuery repeated fields
`precision`	M	Specifies the number of decimal places to use when making calculations for Looker symmetric aggregates
`primary_key`	D	Declares a dimension as the primary key of a view
`required_access_grants`	D DG F M P	Limits access to the field to only users whose user attribute values match the access grants
`required_fields`	D M	Requires that additional fields are added to a query when a field is chosen
`sql_distinct_key`	M	Defines the unique entities over which a measure of `type: sum_distinct` or `type: average_distinct` will be calculated
Value and Formatting Parameters
`case`	D	Creates a discrete set of values a dimension can have determined by SQL conditions
`default_value`	F P	Specifies a default value for filter fields
`direction`	M	Determines the direction that a measure of `type: percent_of_total` or `type: running_total` is calculated when pivots are used
`end_location_field`	D	Defines the field that contains the end location for a field of `type: distance`
`html`	D DG M	Modifies the HTML output of a field using Liquid templating
`list_field`	M	Declares the dimension from which a measure of `type: list` will be calculated
`percentile`	M	Specifies the fractional value (the Nth percentile) for a measure of `type: percentile` or `type: percentile_distinct`
`sql`	D DG M F	Determines how a field will be calculated
`sql_end`	D DG	Defines the end time of a duration for a duration type dimension group or a duration type dimension
`sql_latitude`	D	Defines the latitude of a dimension of `type: location`
`sql_longitude`	D	Defines the longitude of a dimension of `type: location`
`sql_start`	D DG	Defines the begin time of a duration for a duration type dimension group or a duration type dimension
`start_location_field`	D	Defines the field that contains the start location for a field of `type: distance`
`tiers`	D	Defines the tiers for a dimension of `type: tier`
`type` (for dimension, filter, or parameter)	D F P	Specifies the type of dimension, filter, or parameter
`type` (for dimension group)	DG	Specifies the type of dimension group
`type` (for measure)	M	Specifies the type of measure
`string_datatype`	D	Specifies the unicode data type for a field of `type: string` for SQL Server or MySQL
`units`	D	Specifies the units to use for a field of `type: distance`
`value_format`	D M	Formats the output of a field using Excel style options
`value_format_name`	D M	Formats the output of a field using a built-in or custom format
Visualization Parameters
`allow_fill`	D DG	Determines if dimension filling is allowed for a dimension
`map_layer_name`	D	Specifies a mapping from a data value to a geographic region that you've defined on a built-in or custom map
Parameters to Avoid
`decimals`	D M	Removed 5.4 Replaced by `value_format`
`format`	D M	Removed 3.16 Replaced by `value_format`