Feature enhancement to p:dataTable.
Compare with popular "checkall" box often found above or below row-based checkbox.
Imagine an additional row at the bottom (if possible well aligned on the boundaries
with other column table cells) with space for entering suitable values that will
be applied to all values of all cells in column above.
Could use same "edit pen" and tick (save) cross (cancel) symbols used for row-based in-cell editing.
Somehow on save set is applied to all values in cells in column above special apply-to-all row.
This would save a huge amount of data entry time for some cases.