Jewish_physicists
Let's observe them in MySQL:
mysql enwiki -e "select page_id, page_namespace, page_title, page_is_redirect from page where page_namespace in (0, 14) and page_title in ('Computer_storage_devices', 'Computer_data_storage')"
outputs:
+----------+----------------+--------------------------+------------------+
| page_id  | page_namespace | page_title               | page_is_redirect |
+----------+----------------+--------------------------+------------------+
|     5300 |              0 | Computer_data_storage    |                0 |
| 42371130 |              0 | Computer_storage_devices |                1 |
|   711721 |             14 | Computer_data_storage    |                0 |
|   895945 |             14 | Computer_storage_devices |                0 |
+----------+----------------+--------------------------+------------------+
mysql enwiki -e "select cl_from, cl_to from categorylinks where cl_from in (5300, 711721, 895945, 42371130)"
gives:
+----------+-----------------------------------------------------------------------+
| cl_from  | cl_to                                                                 |
+----------+-----------------------------------------------------------------------+
|     5300 | All_articles_containing_potentially_dated_statements                  |
|     5300 | Articles_containing_potentially_dated_statements_from_2009            |
|     5300 | Articles_containing_potentially_dated_statements_from_2011            |
|     5300 | Articles_with_GND_identifiers                                         |
|     5300 | Articles_with_NKC_identifiers                                         |
|     5300 | Articles_with_short_description                                       |
|     5300 | Computer_architecture                                                 |
|     5300 | Computer_data_storage                                                 |
|     5300 | Short_description_matches_Wikidata                                    |
|     5300 | Use_dmy_dates_from_June_2020                                          |
|     5300 | Wikipedia_articles_incorporating_text_from_the_Federal_Standard_1037C |
|   711721 | Computer_architecture                                                 |
|   711721 | Computer_data                                                         |
|   711721 | Computer_hardware_by_type                                             |
|   711721 | Data_storage                                                          |
|   895945 | Computer_data_storage                                                 |
|   895945 | Computer_peripherals                                                  |
|   895945 | Recording_devices                                                     |
| 42371130 | Redirects_from_alternative_names                                      |
+----------+-----------------------------------------------------------------------+
So we see that cl_from encodes the parent categories:
  • parent categories of categories:
    • en.wikipedia.org/wiki/Category:Computer_data_storage, which has ID 711721, has parent categories: "Computer hardware by type", "Computer data", "Data storage", "Computer architecture". This matches exactly on the database. These are all encoded on the source code of the page:
      {{DEFAULTSORT:Storage}}
      [[Category:Computer hardware by type]]
      [[Category:Computer data|Storage]]
      [[Category:Data storage|Computer]]
      [[Category:Computer architecture]]
    • en.wikipedia.org/wiki/Category:Computer_storage_devices has parent categories: "Computer data storage", "Recording devices", "Computer peripherals". This matches exactly on the database.
  • parent categories of pages:
    • en.wikipedia.org/wiki/Computer_storage_devices whish is a redirect gets the magic category "Redirects_from_alternative_names", a humongous placeholder with many thousands of pages: en.wikipedia.org/wiki/Category:Redirects_from_alternative_names
    • en.wikipedia.org/wiki/Computer_data_storage shows only two categories onthe web UI: "Computer data storage" and "Computer architecture". Both of these are present on the database and at the end of the source code:
      {{DEFAULTSORT:Computer Data Storage}}
      [[Category:Computer data storage| ]]
      [[Category:Computer architecture]]
      The others appear to be more magic. Two of them we can guess from the templates:
      {{short description|Storage of digital data readable by computers}}
      {{Use dmy dates|date=June 2020}}
      are likely Use_dmy_dates_from_June_2020 and Articles_with_short_description but the rest is more magic and not necessarily present in-source.
So to find all articls and categories under a given category title, say en.wikipedia.org/wiki/Category:Mathematics we can run:
mariadb enwiki -e "select cl_from, cl_to, page_namespace, page_title from categorylinks inner join page on page_namespace in (0, 14) and cl_from = page_id and cl_to = 'Mathematics'"
Definition, anywhere on article, likely ideally as the first usage:
<ref name="myname">{{cite web ...}}</ref>
And then you can use it later on as:
<ref name="myname" />
which automatically expands the exact same thing, or using the shortcut:
{{r|myname}}
To cite multiple pages of a book: en.wikipedia.org/wiki/Wikipedia:Citing_sources#Citing_multiple_pages_of_the_same_source, the best method is to define and use the reference without adding the p or location in cite as:
<ref name="googleStory">{{cite book |title=The Google Story}}</ref>{{rp|p=123}}
Do not set the page in cite, otherwise it shows up on the references. Instead we use the {{rp}} template. And then use the reference with the {{r}} template as:
{{r|googleStory|p=456}}
or for multiple pages:
{{r|googleStory|pp=123, 156-158}}
A good big sample definition:
<ref name="googleStory">{{cite book |last1=Vise |first1=David |author-link1=David A. Vise |last2=Malseed |first2=Mark |author-link2=Mark Malseed |title=The Google Story |date=2008 |publisher=Delacorte Press |url=https://archive.org/details/isbn_9780385342728}}</ref>
There is also title-link to link to a wiki page. But it is incompatible with url= for Internet Archive Open Library links which is a shame.
So, it turns out that Wikipedia does have a (ultra obscure as usual) mechanism for pull requests. You learn a new one every day.
OMG they have that. Slightly slightly overlap with OurBigBook.com.