The real wordsTheory
The calculated column
Calculated columnA new column added to a table, computed row by row at refresh and stored in the model.
It works in row context: while the formula runs, "the current row" exists, so Sales[Sales] - Sales[Profit] means this row's sales minus this row's profit.
Because it is stored, it behaves exactly like a column that came from the source: it can go on an axis, in a slicer or in a legend, and it costs memory in proportion to the number of rows.
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