擅长:python、mysql、java
<p>你可以这样试试</p>
<pre><code> SELECT month
, monthname(str_to_date(MonthNum,'%m')) Monthname
, year
,country
, sum((cases)/sum(Tests))*100 as caseRate
, sum((affected)/sum(cases))*100 as affectedrate
FROM csv
group by country ,month , Monthname, year
</code></pre>