ALL Returns all the rows in a table, or all the values in a column, ignoring any filters that might have been applied. This function is useful for clearing filters and creating calculations on all the rows in a table.
Syntax
ALL( [table | column[, column[, column[,…]]]] )
Parameters
Table – The table that you want to clear filters on.
Column – The column that you want to clear filters on.
Return Value
The table or column with filters removed.
Reference Data
https://docs.microsoft.com/en-us/dax/dax-function-reference