MAX, MAXA, MAXX – DAX Guide

MAX: Returns the largest value in a column, or the larger value between two scalar expressions.
https://dax.guide/max/

MAXA: Returns the largest value in a column.
https://dax.guide/maxa/

MAXX: Returns the largest value that results from evaluating an expression for each row of a table. Strings are compared according to alphabetical order.
https://dax.guide/maxx/

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