FIRSTDATE

Returns the first date in the current context for the specified column of dates.

Syntax

FIRSTDATE(<dates>)  

Parameters

Term Definition
dates A column that contains dates.

Return value

A table containing a single column and single row with a date value.

Remarks

  • The dates argument can be any of the following:

    • A reference to a date/time column.
    • A table expression that returns a single column of date/time values.
    • A Boolean expression that defines a single-column table of date/time values.
  • Constraints on Boolean expressions are described in the topic, CALCULATE function.

  • When the current context is a single date, the date returned by the FIRSTDATE and LASTDATE functions will be equal.

  • The Return value is a table that contains a single column and single value. Therefore, this function can be used as an argument to any function that requires a table in its arguments. Also, the returned value can be used whenever a date value is required.

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

Example

The following sample formula creates a measure that obtains the first date when a sale was made in the Internet sales channel for the current context.

= FIRSTDATE('InternetSales_USD'[SaleDateKey])  

Date and time functions
Time intelligence functions
LASTDATE function
FIRSTNONBLANK function