SQL

mysql group by month

select count(*), DATE_FORMAT(timestamp, "%Y-%m-01")
from title
group by DATE_FORMAT(timestamp, "%Y-%m-01")

mysql group by day

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

mysql group by day

GROUP BY DATE_FORMAT(created_at, '%Y%m%d')

mysql group by date

SELECT SUM(foo), DATE(mydate) FROM a_table GROUP BY DATE(a_table.mydate);