Add data to existing data in MySQL Database - php

Question

I have a table called tblActivities. There are two fields ID and Attendees.
ID Attendees
1 Jon Jhonson
2 Ive Iveson
Which PHP function or MySQL statement do I need to use to get to this result:
ID Attendees
1 Jon Jhonson, Ive Iveson, Adam Adamer
2 Ive Iveson
In other words, how can I add new data to existing data in my database?

Answer 1

You need something like:
UPDATE tblActivities
SET Attendees = CONCAT(Attendees, "Ive Iveson, Adam Adamer")
WHERE id = 1;
But maybe you should change the database layout. It is preferable to have only one value in one field. You could find more information under http://en.wikipedia.org/wiki/Database_normalization.

Answer 2

use mysql's update statement. If you want to exeute through php then
first get the existing value using select statement,
SELECT Attendees from <table-name> WHERE ID = 1
you will get attendees existing value, put it in a php variable, now concatenate your value..
and then update,
UPDATE <table_name>
SET Attendees=<new-value>
WHERE ID=1
you would have to use the php's mysql functions to run the above queries

Answer 3

I think you're better off restructuring. Make a table:
ID (primary key)
ACTIVITY_ID (foreign key to activity table)
ATTENDEE (foreign key to USERS table)
Then select everything from that event and concat in PHP.
$q = mysql_query( 'SELECT ATTENDEE FROM tblActivities '.
'WHERE ACTIVITY_ID = $activity_id' );
$attendees = array();
while( $row = mysql_fetch_assoc( $q ) )
{
$attendees[] = $row['attendee'];
}
$attendees =implode( ' ', $attendees );