php - Finding out the sum amount from fields that are associated with dates before a given date

Question

I have the following table in my database. Now what I want to find out is the total sum amount that are associated with dates before 04-01-2012 from the field "amount".

id        Date            Amount
1      02-01-2012          500 
2      03-01-2012          500 
3      04-01-2012          500 
4      25-01-2012          500 
5      10-02-2012          500 
6      21-03-2012          500 

If I calculate it manually then the result would be: 500( Date: 02-01-2012)+ 500 (Date: 03-01-2012)= 1000.

Would you please kindly help me with the mysql query?

Thanks in Advance :)

Answer 1

SELECT SUM(Amount) FROM your_table WHERE `Date` < DATE('04-01-2012')

Answer 2

Select Sum(Amount) `Total` From table where `Date` < DATE(`04-01-2012`);

Answer 3

像这样的东西是最好的：

SELECT SUM(`Amount`) AS `Total` FROM `table` WHERE `Date` < DATE('2012-01-04')

将返回：

Total  
1000