SELECT

    COUNT(id) AS num,

    DATE_FORMAT(create_time, '%Y-%m') AS createTime

FROM

    table

WHERE

    create_time >= '2016-01-01 00:00:00'

        AND create_time < '2017-01-01 00:00:00'
## 如果已经确定了时间没必要group by year 再group by month了

## GROUP BY DATE_FORMAT(create_time, '%Y') , DATE_FORMAT(create_time, '%Y%m')

GROUP BY DATE_FORMAT(create_time, '%Y%m')

ORDER BY createTime