Question

// Get Id, Streamanbieter und StreamId
$sql = mysql_query("SELECT `Id`,`Anbieter`,`StreamId`,`Online` FROM `streams`");

// Aktualisiere streams
while($row = mysql_fetch_object($sql)) {
    $id              = $row->Id;
    $anbieter        = $row->Anbieter;  
    $streamid        = $row->StreamId;
    $ison            = $row->Online;
    $set_online      = "UPDATE streams Set Online = '1' WHERE Id = $id";
    $set_offline     = "UPDATE streams Set Online = '0' WHERE Id = $id";
    //$set_onlinesince = "UPDATE streams SET Online_since = current_timestamp WHERE Id = $id AND Online_since = '0000-00-00 00:00:00'";
    $viewers         = get_viewers($streamid, $anbieter);
    $update_viewers  = "UPDATE streams Set Viewers = $viewers WHERE Id = $id";
    $set_zero        = "UPDATE streams Set Viewers = 0 WHERE Id = $id";
    $set_datezero    = "UPDATE streams Set Online_since = '0000-00-00 00:00:00' WHERE Id = $id";
    if(get_online($streamid, $anbieter) == true) {
        if($ison == 0) {
            //mysql_query($set_onlinesince);
        }
        mysql_query($set_online);
        mysql_query($update_viewers);   
    }
    else {
        mysql_query($set_offline);
        mysql_query($set_zero);
        mysql_query($set_datezero); 
    }
}

Check out the commented lines $set_onlinesince. I had the problem that mysql_query($set_onlinesince) was executed nearly all the time, so I made the IF clause and added an additional statement in the Where clause. It was executed most of times.
After that I made an echo into the IF clause. When I executed the file it didn’t show the echo output but would execute the mysql_query($set_onlinesince). Then I tried to outcomment the line and it still was executed. When I outcomment the variable with the query and it was still executed after page reload. That does freak me out.
I deleted the cache in my browser several times and also tried it in a different browser. There was no effect.
How can this happen???

Answer 1

It could be possible in this scenario that the field is set to ON UPDATE CURRENT_TIMESTAMP, which would update it automatically with one of the previous queries.