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

Hover over a parameter name to see a quick description; click it to jump to that 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 on hover
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	Shows suggestions to users when sql_always_where is in use, and do apply those limits to the suggestions
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 datatype 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