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Comment: Published by Scroll Versions from space DEV and version r0810

D toc

Excerpt

Extracts the set of unique values from a column into an array stored in a new column. This function is typically part of an aggregation. 

Tip

Tip: To generate unique values for the generated array, apply the ARRAYUNIQUE function in the next step after this one. See ARRAYUNIQUE Function.

Input column can be of any type.

  • By default, the list is limited to 1000 values. To change the maximum number of values, specify a value for the limit parameter.
  • This function is intended to be used as part of an aggregation to return the unique set of values by group. See Pivot Transform.

For a version of this function computed over a rolling window of rows, see ROLLINGLIST Function.

D s lang vs sql

D s
snippetBasic

D lang syntax
RawWrangletrue
Typeref
showNotetrue
WrangleTextpivot value:unique(Name, 500) group:Month limit:1

unique(Name, 500)

Output: Returns the unique values for Name in an array of all values (up to a count of 500).

D s
snippetSyntax

D lang syntax
RawWrangletrue
Typesyntax
showNotetrue
WrangleTextpivot value:unique(function_col_ref, [limit_int]) [ group:group_col_ref] [limit:limit_count]

unique(function_col_ref, [limit_int]) [ group:group_col_ref] [limit:limit_count]


ArgumentRequired?Data TypeDescription
function_col_refYstringName of column to which to apply the function
limit_intNinteger (positive)Maximum number of unique values to extract into the list array. From 1 to 1000.

For more information on the group and limit parameters, see Pivot Transform.

D s lang notes

function_col_ref

Name of the column from which to extract the list of unique values based on the grouping.

  • Literal values are not supported as inputs.
  • Multiple columns and wildcards are not supported.

D s
snippetusage

Required?Data TypeExample Value
YesString (column reference)myValues

limit_int

Non-negative integer that defines the maximum number of unique values to extract into the list array. 

Info

NOTE: If specified, this value must between 1 and 1000, inclusive.

Info

NOTE: Do not use the limiting argument in a unique function call on a flat aggregate, in which all values in a column have been inserted into a single cell. In this case, you might be able to use the limit argument if you also specify a group parameter. Misuse of the unique function can cause the application to crash.

D s
snippetusage

Required?Data TypeExample Value
NoInteger50


D s
snippetExamples

Example - Colors sold this month

Include Page
EXAMPLE - LIST and UNIQUE Function
EXAMPLE - LIST and UNIQUE Function

D s also
labelaggregate