trouble deleting column from table

[pcw]

Hi, I have this script which I would like to delete a column from a table. I cant seem to get it right although it gives no errors.

 

case "deletefield":

include_once("data/mysql.php");

$fieldName = $_GET['fieldName'];
$mysqlPassword = (base64_decode($mysqlpword));

$con = mysql_connect("$localhost", "$mysqlusername", "$mysqlPassword") or die(mysql_error());
mysql_select_db("$dbname", $con) or die(mysql_error());
mysql_query("DELETE FROM profiles WHERE $fields = mysql_num_fields('$fieldName')");

mysql_close($con);

header("Location: admin.php?cmd=profileFields&username=admin");

break;

 

$fieldName is carried to the form correctly, I just cant work out the code for $fields = mysql_num_fields

 

Any help is much appreciated

[The Little Guy]

Try this:

 

mysql_query("DELETE FROM profiles WHERE $fields = ".mysql_num_fields('$fieldName'));

[pcw]

Hi, thanks for your reply. I tried this and now get these errors:

 

Warning: mysql_num_fields(): supplied argument is not a valid MySQL result resource in /home/tropicsb/public_html/MemberSiteMaker/admin.php on line 621

 

Warning: Cannot modify header information - headers already sent by (output started at /home/tropicsb/public_html/MemberSiteMaker/admin.php:621) in /home/tropicsb/public_html/MemberSiteMaker/admin.php on line 624

 

thanks

[The Little Guy]

Oops, I put quotes around $fieldName, you should remove them

 

NVM still an error

[PFMaBiSmAd]

A DELETE query will delete a ROW from your table.

 

If you want to remove an actual column from your whole table, you would use an ALTER TABLE query.

 

If you want to clear the value in a column in one or more rows in your table, you would use an UPDATE query.

 

What exactly are you trying to accomplish?

[pcw]

I am trying to remove an actual column from the profiles table, but am still having no luck 

[PFMaBiSmAd]

Check out the DROP COLUMN syntax at this link - http://dev.mysql.com/doc/refman/5.1/en/alter-table.html

[pcw]

Hi PFMaBiSmAd, thanks very much for pointing me in the right direction, problem solved :-)

 

mysql_query("ALTER table profiles DROP column $fieldName");