+------------+---------------+------------------------+
|     n      | n_mobileview  | n_mobileview_pct_of_n  |
+------------+---------------+------------------------+
| 656646289  | 4765973       | 0.7258                 |
+------------+---------------+------------------------+

select
    count(*) as n,

    count(if(uri_query like '%mobileview%', 1, null)) as n_mobileview,
    round(100 * count(if(uri_query like '%mobileview%', 1, null)) / count(*), 4) as n_mobileview_pct_of_n
from
    wmf.webrequest
where
    year = 2018
    and month = 11
    and day = 28

    and uri_path = '/w/api.php'
;