update 1 table compare 2 tables query

[knightsjoker]

Hi guys,

 

I'm stump on how to do this.  Basically I'm trying to update 1 table by comparing values from different tables.

 

here's how i set it up:

 

 
$query = "SELECT booking_event.starting_date_time, booking_schedule.schedule_date_time ".
"FROM booking_event, booking_schedule ".
    "WHERE booking_event.starting_date_time = booking_schedule.schedule_date_time";

 

with that part set...

i want to update a different field which is event_id_location_# (there are 20 locations)

I want to update just certain location according to the schedule_date_time

 

so let's say location 1 has a value of 1 (occupied)  I want to update it to 0 (not occupied)

 

how do I go about doing this?  I already passed the hidden value of location (is it correct?):

 
<a href=\"delete.php?id={$row[id]}&passlocation={$getlocation}\">Delete</a>"; ?>

 

I was thinking of if function.

 
while($row = mysql_fetch_array($query))
{
    if (location == loc1)
    {
        $query2="UPDATE booking_schedule SET event_id_location_1 = '0'";
    }
}

 

thanks guys

[premiso]

Why not just do this:

 

if (isset($_GET['passlocation'])) {
    mysql_query("UPDATE booking_schedule SET event_id_location_" . (int) $_GET['passlocation'] . " = '0' WHERE id = '" . (int) $_GET['id'] . "'");
}

 

I would suggest doing data checks on the $_GET, but yea. In the one you posted, without the where, every row in that table would be set to 0.