php - way to check for if sql row exists?

464

my problem is this

i am fetching a mysql row via this

                $sql_istorrenthere = $this->query_silent("SELECT media_type
FROM " . DB_PREFIX . "auction_media WHERE
                auction_id='" . $item_details['auction_id'] . "'"); 
$row = mysql_fetch_array($sql_istorrenthere);

and then calling it with this

if ($row['media_type'] == 4) 
{

        $display_output = GMSG_TORRENT;}
        else
        {
        $display_output = GMSG_NOTORRENT;
        }
}

however, media_type has multiple values, (1,2,3,4) how to write it so that it checks if 4 exists? because now i believe it is checking if media_type equals 4 and that is false, which is giving me the wrong display_output

202

Answer

Solution:

You can use mysql_num_rows to determine if any rows were returned, and this works by adding a search condition in your query adding " AND media_type = 4" to the end

if(mysql_num_rows($sql_istorrenthere)) {

} else {

}

// You can loop through records by doing the following, this prints out every media type :)
while ($row = mysql_fetch_array($sql_istorrenthere)) {
    echo $row['media_type'] . '<br />';
}

902

Answer

Solution:

You can just add on "AND media_type = '4'" to your query. But you really should use paramaterized queries.

Once your query has "AND media_type = '4'" you can check RowCount.

661

Answer

Solution:

There are probably better ways, but here's one idea.

$media_type_ids = explode(',', $row['media_type']);
if (array_search(4, $media_type_ids) !== FALSE) {
    // found
}

It could be possible to even do this in-situ in the database query ... potentially.

730

Answer

Solution:

// Comment the next line after you get what it is
@print ("Value of media type is: >>>".$row['media_type']."<<<"); // Line to be commented

if (isset($row['media_type']) && $row['media_type'] == 4) {
  $display_output = GMSG_TORRENT;
}
else {
  $display_output = GMSG_NOTORRENT;
}

To fetch all media types:

<?php
$sql_istorrenthere = $this->query_silent("SELECT media_type FROM " . DB_PREFIX . "auction_media"); 
while ($row = mysql_fetch_array($sql_istorrenthere)) {
// Comment the next line after you get what it is
  @print ("Value of media type is: >>>".$row['media_type']."<<<"); // Line to be commented

  if (isset($row['media_type']) && $row['media_type'] == 4) {
    $display_output = GMSG_TORRENT;
  }
  else {
    $display_output = GMSG_NOTORRENT;
  }

}

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