--- Vijayaraghavan R <[EMAIL PROTECTED]> wrote:

> I am a newbie php user.
> 
> I use PHP & MYSQL. I want to store a date field in MYSQL using PHP & later
> do some checking for dates greater than or less than the stored date.
> 
> Can someone help me on how to do this?
> 
> Thanks & Regards,
> R.Vijay

Note that the available date range for MySQL is very generous, Jan 1, 1000 to
Dec 31, 9999.  However, in a practical sense the dates which work well in PHP
in the current operating systems ends up being between Jan 1 1970 and some date
around 2040.  If you have a lot of historical dates which are before 1970, you
should do your date calculations and comparisons in MySQL queries.  If they are
all after 1970 then you can use either MySQL or PHP.  Don't forget about
birthdates which are very likely to be before 1970 for many applications.

Dates which are formatted as YYYY-MM-DD HH:MM:SS can be compared directly as
strings.

You can also use things like UnixTime to calculate the number of seconds after
a certain important date (1 Jan 1970 for Unix/Linux/OS X).  These are expressed
as integers.

In a MySQL query you can literally compare one date field with another using
the > or < signs.  You can also compare against a constant in the format I
described above with HH being in 24 hour time, of course.  If time zones are
important then it is best to keep everything in UTC.

For PHP you can compare values in the above format directly as strings or you
can convert a date to UnixTime with functions like strtotime().

There is a wide selection of tools to use.  For us to help you better, you need
to pose specific questions and example data.

James

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