e-commerce problem

elle_girl · 2005-02-13T13:02:27+00:00

I occur this problem at add_cart.php script <?php // This page adds prints to the shopping cart. session_start(); if (is_numeric ($_GET['pid'])) { // C...

e-commerce problem

Roger_Ramjet

The error message means that your query failed. Add a line to echo $query BEFORE it is run, then we can see what is wrong with the SQL syntax. But check for typos in your table names etc as well.

bodzan

...as you can see when I posted code lines they are highlighted so are more readable...

Learn how to do it here

Show us which line is 57 of view_cart.php file and where is your sql statement which result is used in line 57...

elle_girl

This is the script for line 57

while ($row = mysql_fetch_array ($result, MYSQL_ASSOC)) {

Weedpacket

Originally posted by bodzan
...and where is your sql statement which result is used in line 57...

elle_girl

// Retrieve all of the information for the prints in the cart.
$query = 'SELECT * FROM category, product WHERE category.category_id = product.category_id AND product.product_id IN (';
foreach ($_SESSION['cart'] as $key => $value) {
$query .= $key . ',';
}
$query = substr ($query, 0, -1) . ') ORDER BY category.last_category ASC';
$result = mysql_query ($query);

bodzan

It might get you an idea what's wrong with it as Roger suggested...

elle_girl

It cannot appear the one that store before as got problem with the error in sql.
Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in C:\Program Files\Apache Group\Apache2\htdocs\view_cart.php on line 57

The array that print looks like these
Array
(
[cart] => Array
(
[pid] => 1
)

)

bodzan

... therefore there won't be any result to give you an error...

Or better, yet: to comment the line 57 that gives you an error...

Roger_Ramjet

If you are going to ask for help then you might at least listen to our requests and act on them

USE THE PHP TAGS TO HIGHLIGHT YOUR CODE

<?php
// This page displays the contents of the shopping cart.
session_start();
// Set the page title and include the HTML header.
$page_title = 'View Your Shopping Cart';
include_once ('includes/header_customer_two.html');

// Check if the form has been submitted (to update the cart)
if (isset ($_POST['submit'])) {

foreach ($_POST['qty'] as $key => $value) {
if (($value == 0) AND (is_numeric ($value))) {
unset ($_SESSION['cart'][$key]);
} elseif ( is_numeric ($value) AND ($value > 0) ) {
$_SESSION['cart'][$key] = $value;
}
}
}

// Check if the shopping cart is empty.
$empty = TRUE;
if (isset ($_SESSION['cart'])) {
foreach ($_SESSION['cart'] as $key => $value) {
if (isset($value)) {
$empty = FALSE;
}
}
}

// Display the cart if it's not empty.
if (!$empty) {

require_once ('./mysql_connect.php'); // Connect to the database.

// Retrieve all of the information for the prints in the cart.
$query = 'SELECT * FROM category, product WHERE category.category_id = product.category_id AND product.product_id IN (';
foreach ($_SESSION['cart'] as $key => $value) {
$query .= $key . ',';
}
$query = substr ($query, 0, -1) . ') ORDER BY category.last_category ASC';

//  Your error says that $result is not a valid resultset: THAT MEANS THE QUERY FAILED
// ---------------- ECHO THE QUERY AS REQUESTED BY US ---------

echo $query;

// ---------------- THEN POST IT SO WE CAN SEE WHAT IT SAYS

$result = mysql_query ($query);     

// Create a table and a form.
echo '<table border="0" width="90%" cellspacing="3" cellpadding="3" align="center">
<tr>
<td align="left" width="30%"><b>Author</b></td>
<td align="left" width="30%"><b>Book Title</b></td>
<td align="right" width="10%"><b>Price</b></td>
<td align="center" width="10%"><b>Qty</b></td>
<td align="right" width="10%"><b>Total Price</b></td>
</tr>
<form action="view_cart.php" method="post">
';

// Print each item.
$total = 0; // Total cost of the order.
while ($row = mysql_fetch_array ($result, MYSQL_ASSOC)) {  // LINE 57

// Calculate the total and subtotals.
$subtotal = $_SESSION['cart'][$row['product_id']] * $row['price'];
$total += $subtotal;

// Print the row.
echo " <tr>
<td align=\"left\">{$row['first_category']} {$row['middle_category']} {$row['last_category']}</td>
<td align=\"left\">{$row['product_name']}</td>
<td align=\"right\">\${$row['price']}</td>
<td align=\"center\"><input type=\"text\" size=\"3\" name=\"qty[{$row['product_id']}]\" value=\"{$_SESSION['cart'][$row['product_id']]}\" /></td>
<td align=\"right\">$" . number_format ($subtotal, 2). "</td>
</tr>\n";
} // End of the WHILE loop.

// Print the footer and close the table and the form.
echo ' <tr>
<td colspan="4" align="right"><b>Total : <b></td>
<td align="right">$' . number_format ($total, 2) . '</td>
</tr>
</table><div align="center"><input type="submit" name="submit" value="Update My Cart" /></form><br /><br /><a href="checkout.php"><font size="+3">Continue To Purchase</font></a></div>';

mysql_close(); // Close the database connection.

} else {
echo '<p>Your cart is currently empty.</p>';
}

?>
<PRE><?php
print_r($_SESSION);
?></PRE>

Now stop arguing and just do as we said.

elle_girl

SELECT * FROM category, product WHERE category.category_id = product.category_id AND product.product_id IN (pid) ORDER BY category.last_category ASC

Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in C:\Program Files\Apache Group\Apache2\htdocs\view_cart.php on line 58

bodzan

The problem really is in query:

SELECT * FROM category, product WHERE category.category_id = product.category_id AND product.product_id IN (pid) ORDER BY category.last_category ASC

pid means nothing to MySQL. If you wanted it to be a value as a string it has to be quoted with single quotes (')...

If you need it to be a number then something went wrong because clearly you don't have a number there...

Forgive Roger on his harsh words, but he has the point: the code is just too hard to analyze when it is not printed with PHP highlighting...
Again, to learn how to use VB code that allows you to do it go here...

Even if it is a small part of code, but to have this large part of code just printed out, it's impossible to see everything...
It may be O.K. for you to look at it, because you wrote it, but for us - it is hard and many won't even bother...

elle_girl

// Retrieve all of the information for the prints in the cart.
$query = 'SELECT * FROM category, product WHERE category.category_id = product.category_id AND product.product_id IN (";

[COLOR=red]//The error says at this line[/COLOR] foreach ($_SESSION['cart'] as $key => $value) {
	[COLOR=blue]$query .= $key . ',';
}[/COLOR]
[COLOR=green]$query = substr ($query, 0, -1) . [COLOR=red]"[/COLOR]) ORDER BY category.last_category ASC';[/COLOR]
[COLOR=orange]echo $query;[/COLOR]
[COLOR=green]$result = mysql_query ($query);[/COLOR]

I make changes on the red colour. The previous script it uses single quote but when try use double quote appear this problem

Parse error: parse error in C:\Program Files\Apache Group\Apache2\htdocs\view_cart.php on line 37

Roger_Ramjet

You do not want the NAME of the variable ($key) you want the VALUE ($value). Try this

// Retrieve all of the information for the prints in the cart.
$query = "SELECT * FROM category, product WHERE category.category_id = product.category_id AND product.product_id IN (";

foreach ($_SESSION['cart'] as $key => $value) {
$query .= $value . ",";
}
$query = substr ($query, 0, -1) . ") ORDER BY category.last_category ASC";
echo $query;
$result = mysql_query ($query);

Roger_Ramjet

I personally prefer explicit joins as they make it more portable as many db engines are stricter with their SQL syntax; and the USING form makes it more obvious what is going on,

// Retrieve all of the information for the prints in the cart.
$query = "SELECT * FROM category INNER JOIN product USING (category_id) WHERE product.product_id IN (";

foreach ($_SESSION['cart'] as $key => $value) {
$query .= $value . ",";
}
$query = substr ($query, 0, -1) . ") ORDER BY category.last_category ASC";
echo $query;
$result = mysql_query ($query);

I kid myself that it will also execute faster: maybe someone can tell me otherwise.

elle_girl

After I try the suggestion one that got use INNER JOIN.
It's appear this problem

Notice: Undefined index: 1 in C:\Program Files\Apache Group\Apache2\htdocs\view_cart.php on line 67

Notice: Undefined index: 1 in C:\Program Files\Apache Group\Apache2\htdocs\view_cart.php on line 75

Line 67

$subtotal = $_SESSION['cart'][$row['product_id']] * $row['price'];

Line 75

Please help me to figure out this problem!

tsinka

Hi,

how does $_SESSION['cart'] look now with

print_r($_SESSION['cart']);

Thomas

elle_girl

It appear this
Your cart is currently empty.

Notice: Undefined index: cart in C:\Program Files\Apache Group\Apache2\htdocs\view_cart.php on line 95

Line 95 is

print_r($_SESSION['cart']);

elle_girl

When I delete teh script
<PRE><?php
print_r($_SESSION);
?></PRE>

It can appear both the error and the result that we want. But the error is same that i post before. The error that regarding pid. Please help me to solve the problem.

tsinka

Please post the current versions of the following files (as attached zip file):

add_cart.php
browse_prints.php
view_cart.php
view_print.php

Thomas

elle_girl

Here I attach the script that request.