Question

Ive spent 4 hours trying to write a simple insert a datetime into a DB, re-read that value and see how much time elapsed. I have seen horrifying example after example in PHP (my ISP only has PHP 5.2.1) not 5.3. Well, after hours of reading.. I found a solution that makes me happy but I dont know how to get it working in the way I need it to work… the code is…

create temporary table Data
( dt DateTime );

insert Data values
    (now() - INTERVAL 23 MINUTE);

select
    TIME_FORMAT(
      TIMEDIFF(now(), dt)
     ,'%i minute(s) ago'
   )
from Data;

I’m using PREPARED statements (PS)… I don’t know how to convert that to procedural style, PS. I was thinking instead of the ? I would put now() but then I had no idea what to put in the value. I thought also… i’ll just change the DB to an INT and then just stick the PHP time() value in there and do some math on it when I read it. Thats my other option but… this will make the SQL do the “work” so… can this be converted to PS?

Thank you!

All I want to do is…

update a record with now() THEN find out how much time has elapsed since I wrote that record and delete it if enough time has passed.

A website showing the code above working is…

http://sqlize.com/r1mlXcM62V

Answer 1

It’s been a whole day of struggling to figure this all out and it looks like I did it. The weird thing is SQL is actually very easy, PHP is very easy. I am old and my brain is rusty (havnt programmed for 17+ years). I visualize how it’s supposed to work in my head and something that should take seconds takes hours to research and figure out. SO… I found a solution…

$query = "SELECT TIMESTAMPDIFF(MINUTE, `sesstoken1created`,now()) FROM pcssecurity";

except I have to change it to a DELETE statement so I was thinking…

$query = "DELETE FROM pcssecurity WHERE TIMESTAMPDIFF(MINUTE, `sesstoken1created`,now()) > 16";

That will delete all timestamps found > 16 min old. Works. I also was researching what to do if there was NO variables to bind.. would it be ok to not include a BIND variables… and appearently it works without bind variables.

SOLUTION

$dbc = mysqli_connect(DB_HOST, DB_USER, DB_USER_PASSWORD, DB_NAME) or die(DB_CONNECT_ERROR .  __LINE__);
$stmt = mysqli_stmt_init($dbc);

$query = "DELETE FROM tablename WHERE TIMESTAMPDIFF(MINUTE, `datetimefieldhere`,now()) > " . SESSION_TOKEN_EXPIRES_IN_MINUTES;
$result = mysqli_stmt_prepare($stmt, $query);
$result = mysqli_stmt_execute($stmt);
$result = mysqli_stmt_affected_rows($stmt);

if ($result === -1) { // some error happened
    die('CreateNewToken insert failed');
}