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SAMPLE

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Applies to: Calculated column Calculated table Measure Visual calculation

Returns a sample of N rows from the specified table.

Syntax

SAMPLE(<n_value>, <table>, <orderBy_expression>, [<order>[, <orderBy_expression>, [<order>]]…])

Parameters

Term Definition
n_value The number of rows to return. It is any DAX expression that returns a single scalar value, where the expression is to be evaluated multiple times (for each row/context). If a non-integer value (or expression) is entered, the result is cast as an integer.
table Any DAX expression that returns a table of data from where to extract the 'n' sample rows.
orderBy_expression Any scalar DAX expression where the result value is evaluated for each row of table.
order (Optional) A value that specifies how to sort orderBy_expression values, ascending or descending: 0 (zero), sorts in descending order of values of order_by. 1, ranks in ascending order of order_by.

Return value

A table consisting of a sample of N rows of table or an empty table if n_value is 0 (zero) or less. If OrderBy arguments are provided, the sample will be stable and deterministic, returning the first row, the last row, and evenly distributed rows between them. If no ordering is specified, the sample will be random, not stable, and not deterministic.

Remarks

  • If n_value is 0 (zero) or less then SAMPLE returns an empty table.

  • In order to avoid duplicate values in the sample, the table provided as the second argument should be grouped by the column used for sorting.

  • This function is not supported for use in DirectQuery mode when used in calculated columns or row-level security (RLS) rules.