instruction: statistics on user displaynames per reputation. shows number of users per reputation group (logarithm) that kept their default username or changed it.
response: SELECT *, ROUND(CAST('default' AS FLOAT) / 'total' * 100, 1) AS percentage FROM (SELECT SUM(CASE WHEN DisplayName = 'user' + CAST(Id AS TEXT) THEN 1 ELSE 0 END) AS "default", SUM(CASE WHEN DisplayName LIKE 'user%' AND NOT DisplayName = 'user' + CAST(Id AS TEXT) THEN 1 ELSE 0 END) AS "merged?", SUM(CASE WHEN NOT DisplayName LIKE 'user%' THEN 1 ELSE 0 END) AS "custom", COUNT(*) AS total, ROUND(LN(Reputation), 0) AS "log(reputation)" FROM Users GROUP BY ROUND(LN(Reputation), 0)) AS data ORDER BY 5