Deleting rows in a database using select lists.

[yc022]

Hi all, this is my first time using this so i'm not really sure how it works. please bear with me.

i am trying to delete a row in a database using a select list. First of all i have a query to produce what i would like to be held in the select (dropdown) list. i then create the select list with a delete button. I then try to create the query to delete the selected option from the list from the database, but nothing happens and an error message appears. This error message however is not one of the error messages returned from one of my queries. Please Help!!!! what am i doing wrong?

<?php

$namequery = "SELECT DISTINCT projectnumber
FROM projects";

$result = mysql_query($namequery) or die('Error, query failed');
$count = mysql_num_rows($result);
if ($count > 0){

echo "<form action=\"<$self>\" method=\"post\">";
echo "<select name=\"item\">";

while($result_row = mysql_fetch_array($result)){
echo "<option name=\"item2\">";
echo ($result_row[0]);
echo "</option>";
}
echo "</select>";
echo "<input type=\"submit\" name=\"Delete\" id=\"Delete\" value=\"Delete\" />";
if(isset($_POST['Delete'])){
foreach($_POST[item] as $del){
$query_delete = ("DELETE FROM projects WHERE projectnumber ='".$del."'");
$result = mysql_query($query_delete) or die('Error, query failed');
}
echo "<meta http-equiv=\"refresh\" content=\"0\"; URL=\"AdminProjects.php\">";
echo "Row deleted!";
}
echo "</form>";
}
else{
echo "There are no project numbers in the system";
}
?>

[gauravgmbhr]

Hi all, this is my first time using this so i'm not really sure how it works. please bear with me.

i am trying to delete a row in a database using a select list. First of all i have a query to produce what i would like to be held in the select (dropdown) list. i then create the select list with a delete button. I then try to create the query to delete the selected option from the list from the database, but nothing happens and an error message appears. This error message however is not one of the error messages returned from one of my queries. Please Help!!!! what am i doing wrong?

<?php

$namequery = "SELECT DISTINCT projectnumber
FROM projects";

$result = mysql_query($namequery) or die('Error, query failed');
$count = mysql_num_rows($result);
if ($count > 0){

echo "<form action=\"<$self>\" method=\"post\">";
echo "<select name=\"item\">";

while($result_row = mysql_fetch_array($result)){
echo "<option name=\"item2\">";
echo ($result_row[0]);
echo "</option>";
}
echo "</select>";
echo "<input type=\"submit\" name=\"Delete\" id=\"Delete\" value=\"Delete\" />";
if(isset($_POST['Delete'])){
foreach($_POST[item] as $del){
$query_delete = ("DELETE FROM projects WHERE projectnumber ='".$del."'");
$result = mysql_query($query_delete) or die('Error, query failed');
}
echo "<meta http-equiv=\"refresh\" content=\"0\"; URL=\"AdminProjects.php\">";
echo "Row deleted!";
}
echo "</form>";
}
else{
echo "There are no project numbers in the system";
}
?>

WHAT is the error that u r getting

i thing u r applying foreach on a non-aaray variable
which will not work
either u create multiple selection list box instead of single selection drop down and send multiple values or dont use foreach

but still lemme know the error message

if u need any help in creatin multiple selection list box, and how to send all multiple values to PHP then do write to me

[ak1dnar]

Hi Here is Solution.Just use this coding by changing the SQL Script.
Please Note that here i am using a Table called product.
Columns:
p_id, p_name

In the Select box I am displaying p_name and as the value of the each and every List menu item I am Passing the p_id for deleting purpose.

That means the from the PHP delete section it will fetch this value Attribute.and pass it to the DELETE query. for this you can use your any other column. :) but for better performance, this primary key in my table is a Good idea.

And also no need to use double quotes for PHP echo. use single quotes. Then No need to escape them.

change this line also
[PHP]echo "<meta http-equiv=\"refresh\" content=\"0\"; URL=\"untitled3.php\">";[/PHP]

[PHP]<?php
require 'dbcon.php';
$namequery = "SELECT p_name,p_id
FROM products";

$result = mysql_query($namequery) or die('Error, query failed');
$count = mysql_num_rows($result);
if ($count > 0)
{
echo '<form action="'.$PHP_SELF.'" method="POST">';
echo '<select name="item">';
while($result_row = mysql_fetch_array($result))
{
echo '<option value="'.$result_row[1].'" >';
echo ($result_row[0]);
echo '</option>';
}
echo '</select>';
echo '<input type="submit" name="Delete" id="Delete" value="Delete" />';
echo '</form>';
}
else
{
echo "There are no project numbers in the system";
}

if($_POST['Delete'])
{
$del = $_POST['item'];
$query_delete = ("DELETE FROM products WHERE p_id ='".$del."'");
$result = mysql_query($query_delete) or die('Error, query failed');
echo "<meta http-equiv=\"refresh\" content=\"0\"; URL=\"untitled3.php\">";
}
?>[/PHP]

[yc022]

Hi, the error i am getting is Access Forbidden. You don't have permission to access the requested object so i will defienetly take out the for each loop. It also says the document is either read-protected or not readable by the server.

[yc022]

Hi, thank you for your help. I'm having a go at changing my code just now so will let you know how i get on.

Hi Here is Solution.Just use this coding by changing the SQL Script.
Please Note that here i am using a Table called product.
Columns:
p_id, p_name

In the Select box I am displaying p_name and as the value of the each and every List menu item I am Passing the p_id for deleting purpose.

That means the from the PHP delete section it will fetch this value Attribute.and pass it to the DELETE query. for this you can use your any other column. :) but for better performance, this primary key in my table is a Good idea.

And also no need to use double quotes for PHP echo. use single quotes. Then No need to escape them.

change this line also
[PHP]echo "<meta http-equiv=\"refresh\" content=\"0\"; URL=\"untitled3.php\">";[/PHP]

[PHP]<?php
require 'dbcon.php';
$namequery = "SELECT p_name,p_id
FROM products";

$result = mysql_query($namequery) or die('Error, query failed');
$count = mysql_num_rows($result);
if ($count > 0)
{
echo '<form action="'.$PHP_SELF.'" method="POST">';
echo '<select name="item">';
while($result_row = mysql_fetch_array($result))
{
echo '<option value="'.$result_row[1].'" >';
echo ($result_row[0]);
echo '</option>';
}
echo '</select>';
echo '<input type="submit" name="Delete" id="Delete" value="Delete" />';
echo '</form>';
}
else
{
echo "There are no project numbers in the system";
}

if($_POST['Delete'])
{
$del = $_POST['item'];
$query_delete = ("DELETE FROM products WHERE p_id ='".$del."'");
$result = mysql_query($query_delete) or die('Error, query failed');
echo "<meta http-equiv=\"refresh\" content=\"0\"; URL=\"untitled3.php\">";
}
?>[/PHP]

[gauravgmbhr]

Hi, thank you for your help. I'm having a go at changing my code just now so will let you know how i get on.

Well make sure that the username and password that u using to connect to the DataBase Server have permissions To delete. so contact UR DB-admin To change ur privelages to database
Coz Most of the time The username given to a programmer by the admins of DB does nOt have permission to delete Rows From Table


And Try Avoiding Using Foreach loop when u are not using an array coz PHP 5 Will produce A E-Warning if the argument supplied to Foreach Loop Is Not An array.
And I guess U R Using Php4.XX

[yc022]

Yeah, it's php 4. I managed to get it working so thank you to everyone for your help. The only problem is that my id's are now getting muddled up, but i have seen a thread on this site that will help me fix that. Thank you again.