SQLite3 - Generate histogram using date ranges and ASCII bar

histogram.sql

-- On MacOSX installed SQLite3 to get log function support
-- brew reinstall sqlite3 --with-functions
SELECT load_extension('/usr/local/opt/sqlite/lib/libsqlitefunctions');

SELECT
    DR.start_datetime as date,
    COUNT(*) AS total,
    replace(substr(quote(zeroblob((log(COUNT(*)) + 1) / 2)), 3, log(COUNT(*))), '0', '*') AS bar
FROM
    kx_exports EXP
    LEFT OUTER JOIN date_ranges DR 
    ON EXP.created_at BETWEEN DR.start_datetime AND DR.end_datetime 
GROUP BY
    DR.start_datetime;