Average count of Wikidata item descriptions added by humans (all languages) per day

SQL

SELECT
    AVG(num_revisions) AS average_num_revisions_per_day,
    AVG(avg_comment_length) AS average_avg_comment_length_per_day
FROM (
    SELECT
        date,
        COUNT(rc_timestamp) AS num_revisions,
        AVG(true_comment_length) AS avg_comment_length
    FROM (
        SELECT
            SUBSTRING(rc.rc_timestamp, 1, 8) AS date,
            rc.rc_timestamp,
            LENGTH(
                -- Remove /* */ comments from the comment_text
                REGEXP_REPLACE(cr.comment_text, '/\\*.*?\\*/ ', '') 
            ) AS true_comment_length
        FROM
            recentchanges rc
        JOIN
            comment_recentchanges cr ON rc.rc_comment_id = cr.comment_id
        WHERE
            rc.rc_bot <> 1 AND
            rc.rc_source = "mw.edit" AND
            NOT SUBSTRING(rc.rc_timestamp, 1, 8) = DATE_FORMAT(NOW(), '%Y%m%d') AND
            cr.comment_text NOT LIKE '%quickstatements%' AND
			cr.comment_text LIKE '/* wbsetdescription-add%'
    ) AS latest_non_bot_revisions 
    GROUP BY date
) AS avg_values;
SQL

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