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+This directory holds files obtained/derived from [English Wikipedia](https://en.wikipedia.org/wiki/Main_Page).
+
+# Downloaded Files
+-   `enwiki-20220501-pages-articles-multistream.xml.bz2` <br>
+    Contains text content and metadata for pages in enwiki.
+    Obtained via <https://dumps.wikimedia.org/backup-index.html>.
+    Some file content and format information was available from
+        <https://meta.wikimedia.org/wiki/Data_dumps/What%27s_available_for_download>.
+-   `enwiki-20220501-pages-articles-multistream-index.txt.bz2` <br>
+    Obtained like above. Holds lines of the form offset1:pageId1:title1,
+    providing, for each page, an offset into the dump file of a chunk of
+    100 pages that includes it.
+
+# Dump-Index Files
+-   `gen_dump_index_db.py` <br>
+    Creates a database version of the enwiki-dump index file.
+-   `dump_index.db` <br>
+    Generated by `gen_dump_index_db.py`. <br>
+    Tables: <br>
+    -   `offsets`: `id INT PRIMARY KEY, title TEXT UNIQUE, offset INT, next_offset INT`
+
+# Description Files
+-   `gen_desc_data.py` <br>
+    Reads through pages in the dump file, and adds short-description info to a database.
+-   `desc_data.db` <br>
+    Generated by `gen_desc_data.py`. <br>
+    Tables: <br>
+    -   `pages`:     `id INT PRIMARY KEY, title TEXT UNIQUE`
+    -   `redirects`: `id INT PRIMARY KEY, target TEXT`
+    -   `descs`:     `id INT PRIMARY KEY, desc TEXT`
+
+# Image Files
+-   `gen_img_data.py` <br>
+    Used to find infobox image names for page IDs, and store them into a database.
+-   `download_img_license_info.py` <br>
+    Used to download licensing metadata for image names, via wikipedia's online API, and store them into a database.
+-   `img_data.db` <br>
+    Used to hold metadata about infobox images for a set of page IDs.
+    Generated using `get_enwiki_img_data.py` and `download_img_license_info.py`. <br>
+    Tables: <br>
+    -   `page_imgs`: `page_id INT PRIMAY KEY, img_name TEXT` <br>
+        `img_name` may be NULL, which means 'none found', and is used to avoid re-processing page IDs.
+    -   `imgs`:
+            `id INT PRIMARY KEY, name TEXT UNIQUE, license TEXT, artist TEXT, credit TEXT, restrictions TEXT, url TEXT`
+            <br>
+        Might lack some matches for `img_name` in `page_imgs`, due to licensing info unavailability.
+-   `download_imgs.py` <br>
+    Used to download image files into imgs/.
+
+# Page View Files
+-   `pageviews/pageviews-*-user.bz2`
+    Each holds wikimedia article page view data for some month.
+    Obtained via <https://dumps.wikimedia.org/other/pageview_complete/monthly/>.
+    Some format info was available from <https://dumps.wikimedia.org/other/pageview_complete/readme.html>.
+-   `gen_pageview_data.py` <br>
+    Reads pageview/* and `dump_index.db`, and creates a database holding average monthly pageview counts.
+-   `pageview_data.db` <br>
+    Generated using `gen_pageview_data.py`. <br>
+    Tables: <br>
+    -   `views`: `title TEXT PRIMARY KEY, id INT UNIQUE, views INT`