Question

I have a mySQL database.

I need to count the number of days between two dates.

My client is going to fill an input hm_date with January 1, 1979 via php form to create a new record.

I need a field total_days to calculate the total number of days from hm_date to the present day. I need this field to always update itself with each passing day.

How do I make hm_date to appear with total days and be always updated?

I asume this can be achieved server-side?

Should I use strototime() ?

Answer 1

You’ll want to use MySQL’s DATEDIFF()

DATEDIFF() returns expr1 – expr2 expressed as a value in days from one
date to the other. expr1 and expr2 are date or date-and-time
expressions. Only the date parts of the values are used in the
calculation.

mysql> SELECT DATEDIFF('2007-12-31 23:59:59','2007-12-30');
        -> 1
mysql> SELECT DATEDIFF('2010-11-30 23:59:59','2010-12-31');
        -> -31

Based on your question I think you would want DATE_DIFF(hm_date, CURRENT_DATE). Just make sure hm_date is in YYYY-MM-DD format.