MySQL DATE_ADD - Displaying using PHP

[devilindisguise]

Hello everyone

 

Hoping someone could lend me a hand. I have a form that takes some end-user's details and adds the date and time into a MySQL table of when the form was submitted. I wish to display that date/time + 4 days ahead using PHP.

 

I believe the MySLQ DATE_ADD should do the trick quite nicely. In fact plumbing the following statement into phpMyAdmin gives me exactly the results I require:

SELECT DATE_ADD(`datetime`,INTERVAL 4 DAY) FROM `faults` WHERE fault_id = '51';

However, just having a pig of a time getting this displayed using PHP. I'm sure this is elementary so forgive me. Here's what I had in mind but is no working. Can someone please point me in the right direction:
 

<?php


$date_query = mysqli_query($con, "SELECT DATE_ADD(`datetime`,INTERVAL 4 DAY) FROM `faults` WHERE fault_id = '51'");
while($row = mysqli_fetch_assoc($date_query)){
echo $row ['datetime'];
}
?>

Many thanks for your help and advice.

 

[mac_gyver]

you need to use an alias name in the query. when you ran it in phpmyadmin, the column heading/name for the value was literally - DATE_ADD(`datetime`,INTERVAL 4 DAY), which you could use in the php code (you would have to convert characters not permitted in variable names to underscores though, using print_r($row) will show what it is), but using an alias name is much easier. change your query to - 

SELECT DATE_ADD(`datetime`,INTERVAL 4 DAY) AS dt FROM `faults` WHERE fault_id = '51';

the php to reference the value would be - $row['dt']

[devilindisguise]

Hi mac_gyver

Thanks for your swift response. In typical fashion I wrote this too hastily. Thinking about it what I actually wanted to do is have it so that when the form was filled and submitted both current timestamp and the timestamp + 4 days would be inserted in the the DB. I achieved it thanks to someone who posted the following:

 

http://coursesweb.net/forum/insert-date-after-days-added-now-function-mysql-t32.htm

 

My code therefore now resembles:

 "INSERT INTO faults (datetime, target_date) VALUES (NOW(), DATE_ADD(NOW(), INTERVAL 4 DAY))");

Had to convert the MySQL columns to a TIMESTAMP format but it now does the trick.

 

Thanks