Adds a key column and/or a constant column.
Adds one new column that contains a sequence of increasing number (i.e. a “Key” Column).
Adds some new columns that each contain a constant value (i.e. a “Constant” Column)
To create the “Key” column, you could also use the Calculator Action (use the variable “_n”) but this one is faster. To create the “Constant” columns, you could also use the Calculator Action but this one is faster.