选择该月的最后日期并显示该月内的所有数据

I have a datepicker calendar, so when I select the last date of that month I want it to display all data which are within that month

For example when I select 31-March-2017 it must display data from 1-31 March.

Here is my code...

SELECT sum(income_amount)from income where (income_date Between '". 
    $_POST['transactiondate']. "'  and '". 
    $_POST['transactiondate'] ."') and traditionalcouncil_name='BAKGAGA-BA- MAAKE' AND 
    financialyear_id = '". $Finyear ."'