FIRSTDATE

Article
06/21/2022

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])