Question

I am using following query to show Gross and Net Amount Month & Year-wise:

SELECT DATE_FORMAT(BILLDATE,'MMM-yyyy'), SUM(GROSSAMOUNT), SUM(NETAMOUNT) 
FROM BILLDETAILS GROUP BY MONTH(BILLDATE);

Other columns are displayed correctly except the first one that involves Date_Format. It is displaying MMM-yyyy in all rows instead of the actual Month and Year.

Answer 1

Because 'MMM-yyyy' is not a correct date format. You probably want '%b-%Y'

http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-format