Summary Rows and Paged Data Tables

Question

In terms of best practices and UI patterns:

if there is a summary row (sums, avg, etc) at the bottom of a data table that has paging should the row be a grand summary of the full result set or a summary of just that pages data?

anyone know of any good UI patterns or examples that display the grand total in a summary row for a paged data table?

tnanks

Answer 1

I think it would depend on the meaningfulness of the summary. For many forms of data, the average of one page of paged results is not particularly meaningful, as the pagination is determined by how many rows will fit on one page rather than a meaningful grouping.

If on the other hand, each page represents one month of data, or something else that is meaningful, then a summary row would be appropriate to that page.

In either case, I would expect that the summary of all of the data would be presented in a different place than the bottom of the paged rows, because then you would be repeating the same summary on the bottom of every page. The summary is usually presented at the beginning as an overview.

Answer 2

Not sure how it would work with averages but a practice found in multipage accounting documents is to include the summary of all previous pages in the first row and the summary of all entries so far at the bottom:

Date        Order ID  Amount
_on previous pages_    15.00
2011-09-15  123456      1.00
2011-09-15  123457      1.00
2011-09-15  123458      1.00
_subtotal_             18.00