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Re: Using Tables

for

From: Sailesh Panchang
Date: Feb 14, 2012 11:24AM

Well I disagree with most arguments here against the summary attribute:
It is part of HTML 4 and for a very specific purpose: to help
non-visual users comprehend the structure / organization of a data
table’s content. This applies to tables that have a really complex
structure.
It may also be used to highlight key / salient values or a data range
especially in large or complex tables.

Some tables containing labor / census / financial data, for example,
can become really complex and large. Students, researchers, analysts
etc. need to access such data and may have no means to re-design the
work of other authors.
Consider tables that have more than 5 or 6 columns, that not only use
colspan but also rowspan. Some may even have 3 rows of column headers
and over 20 rows of data. And again data rows may be grouped.
The description for WCAG2 technique H73 is pretty much based on my
input and captures the above thoughts.
Indeed breaking up a complex table into smaller tables is one
solution butthen it may not be possible to convey the complexity,
dimensions and relationships across multiple attributes that the
table-designer intends to portray through one table. Space /
document’s length constraints may also limit the ability of the author
to use multiple data tables in place of one complex table.
More importantly, often tables on the Web are often a replica of
something that appears in print and the Web content author may not
have the liberty to re-design the table.
It is in these situations the summary plays a critical role. It can
certainly be dispensed with for less complex tables.
The problem is that the average developer / content author puts in a
summary attribute because he has been told to. Few grasp or comprehend
how it will be consumed by the end-user: the blind chap using
assistive technology. And that’s why one does not see examples of good
summaries on the Web in the wild.
Just because there are some reckless drivers or because accidents
happen, one does not ban the manufacture, sale and use of cars!
And certainly when there are complex tables in a document (or Web
page) the author always has the liberty to explain the complexities
in a paragraph before / after the table or on a separate linked page
for the benefit of all readers. There is no ban on doing this. If
textual explanation accessible to all users is present, the table
summary attribute may not be required at all or may not have to be
very elaborate.
And yet even with such an explanation, users who cannot see may still
need some extra help because it is indeed very challenging to review
and comprehend complex data structures using text to speech (or
Braille) interface. It is very different from a visual interface. The
summary attribute’s content is really meant for users who cannot see.
And for this reason it is criminal if HTML5 does away with this
important attribute designed to enhance accessibility of complex /
large data table to non-visual users. Perhaps it should be improved
so that an assistive technology user may access it whenever he needs
to and not be forced to read it everytime one navigates to the table.
Sailesh Panchang
Deque Systems
www.deque.com


On 2/10/12, Jared Smith < <EMAIL REMOVED> > wrote:
> On Fri, Feb 10, 2012 at 12:23 PM, Ted wrote:
>> Definitely need a summary for complex tables.
>
> I disagree. A few reasons why I think summary is almost universally a bad
> idea:
>
> 1. If the table is so complex that its structure needs to be explained
> to the user, it's too complex. Period.
>
> 2. Summary is screen-reader only and is forced upon the screen reader
> user each time the table is encountered. With proper table markup, the
> user should be able to quickly navigate the table to determine its
> content and structure, in the same way that sighted users must scan a
> table to determine its content and structure.
>
> 3. Summary is currently not part of HTML5.
>
> 4. Summary is NOT for presenting the purpose or content of the table.
> It's for describing its structure, when necessary (see #1). Probably
> 90% of summary attributes on the web get this wrong. If it's important
> that the purpose or content of the table be presented, this should be
> done in a way that is accessible to everyone (e.g., <caption>, etc.).
>
> It's a rarity to find a summary attribute that does much good. They
> are almost always a waste of time or an excuse for presenting an
> overly complex table. Or both.
>
> And no, I don't have strong feeling on the subject. :-)
>
> Jared
>