Many tables have content in columns that could be used a categories or tags. But the table-content can not be filtered by these categories or tags as it's only possible to sort columns (also that only works for the first tag). Furthermore, a lot of potential useful content is missing or not as well rehashed/structured as it could be.
Why it is a significant problem:
- I found this to be a needed change as it would be very useful for the Events list of https://en.wikipedia.org/wiki/2020_in_science which I suggested to be converted to table on the page's talk page. This would also allow many more features and could make the article shorter for the reader and more useful. In particular what I suggested as tags/categories for rows of the table are: (scientific) "Research field", (recurrent) "Topic", "Category" and "Endeavor-type" (like "simulation" or "projection"). An exemplary table can be found here. Three exemplary use-cases of such filtering would be: only showing "Category-1" and "Category-2" items with topic "Mitochondria", or all items of the Research-field of "Ecology" or only showing "Category-1" and "Category-2" items by default with a e.g. a [show more] button below the table.
- This is one of a series of tasks that would allow (/ improve) converting this list to a table - other issues of this series are linked under "Further issues" below. Such tags/categories would make the list/table much more useful and they could also be used in similar timeline articles/sections as well as for entirely different articles.
- Another exemplary table where this would be useful is "Comparison of display technology" : there "Computer monitor", "TV", etc could be tags. As explained above they can be neither filtered nor sorted by as there are multiple tags instead of only one per row. One exemplary use-case would be filtering by "Mobile phone" under "Typical use". These tags could make a lot of tables a lot more useful, allow for more extensive content and enable new useful content.
Changing the internals of tables so that each row has a unique ID that has a number of categories/tags for its columns. Then make it possible to allow filtering by tags and categories by making them clickable buttons. Then also allow the editors of a table to specify (add) common/suggested and maybe also default filters for the table. These filters could be applied by clicking on some suggested filter-template above the table. Please also see the exemplary table and the 4 exemplary use-cases above. The row-categories would enable buttons for simple hiding/showing items of specific categories.
The watchlist already has filtering as well as a form of tags so this issue would only require adapting / changing these a bit for tables.
Additional suggestions/requests beyond the basic solution:
There are probably many things this would help enable such as transcluding content of tables that have specific tags set.
T258417: Add "add table entry" and "edit row" for the wikitext editors as well as "edit with VisualEditor" functions to tables for simplyifing editing tables
T258382: Fix the display of tables on mobile (responsive web design: when the user taps on a table rotate the screen for a fullscreen view)
T233340: Add sortability to sortable tables for readers of the mobile web site
T181452: Add sortability to tables with "sortable" class in the Android app