[RESOLVED] delete database quantity in get_item form

[cotton]

assume that i have
item --- amount --- button
=> solution
<javascript>
function addthis(the_id) {
document.formi.yourselection.value = the_id
document.formi.submit();
}
</javascript>

item ---
input type="text" name="amount$id" ---
input type="button" onclick="javascript:addThis($id)"
input type="hidden" name="yourselection"

=> submit
=> you get yourselection = id
$selected_amount = "amount".$yourselection;
==> you can put value in session
$HTTP_SESSION_VARS['amount'] = $$selected_amount;

<table width="80%" border="1" align="center" cellpadding="0" cellspacing="1" bordercolor="#CCCCCC">
<tr>
<td width="18%" bgcolor="#E0E2EB"><div align="left">Description : </div></td>
<td width="82%"><? echo $row['description']; ?></td>
</tr>
<tr>
<td bgcolor="#E0E2EB"><div align="left">Item Code : </div></td>
<td><? echo $row['item_code']; ?></td>
</tr>
<tr>
<td bgcolor="#E0E2EB"><div align="left">Category : </div></td>
<td><? echo $row['category']; ?></td>
</tr>
<tr>
<td bgcolor="#E0E2EB"><div align="left">Current quantity : </div></td>
<td><? echo $row['quantity']; ?></td>
</tr>

                            </table>

Required Quantity:
<input type="text" name="quantity" size="4"><br>
<input type="hidden" name="item_code"

how to make it works?

[Kudose]

What?

[leatherback]

Kudose wrote:

What?

I think he is asking for the [man]manual[/man]

[Kudose]

leatherback wrote:

I think he is asking for the [man]manual[/man]

Glad you could get something from that.

:quiet:

[cotton]

view.php

<td><form name="form2" method="get" action="dbView_Item.php">
<table width="80%" border="1" align="center" cellpadding="0" cellspacing="1" bordercolor="#CCCCCC">
<tr>
<td width="18%" bgcolor="#E0E2EB"><div align="left">Description : </div></td>
<td width="82%"><? echo $row['description']; ?></td>
</tr>
<tr>
<td bgcolor="#E0E2EB"><div align="left">Item Code : </div></td>
<td><? echo $row['item_code']; ?></td>
</tr>
<tr>
<td bgcolor="#E0E2EB"><div align="left">Category : </div></td>
<td><? echo $row['category']; ?></td>
</tr>
<tr>
<td bgcolor="#E0E2EB"><div align="left">Current quantity : </div></td>
<td><? echo $row['quantity']; ?></td>
</tr>
<td width="18%" bgcolor="#E0E2EB"> Required Quantity : </td>
<td width="82%">
<input name="c_qty" type="text" id="c_qty" size="10" maxlength="40"></td>
</tr>

                            </table>

dbView.php

<?php
session_start();

mysql_connect("localhost", "root", "") or die("no connection");
mysql_select_db("alatulis") or die("no database");
$description = $POST['description'];
$category = $POST['category'];
$quantity = $POST['quantity'];
$ref = $POST['item_code'];
if ($quantity > 0 ){
$c_qty = $POST['c_qty'];
$co_qty = $POST['co_qty'];

$co_qty = $quantity - $c_qty;

$query = "UPDATE stationary SET  description='$description', category='$category', quantity='$co_quantity' where item_code='$item_code' ";
mysql_query($query) or die("not insert");
}
echo "<SCRIPT>alert('Data has been updated')</script>";
echo "<meta http-equiv=\"refresh\" content=\"0; URL=Home.php\">";

?>

i can't update the quantity..is there something wrong with my code? plus it says undefined index description, quantity etc..

[Roger_Ramjet]

Try using the correct variable names in the query.

[cotton]

the correct variable?it is the correct one..😕

[leatherback]

The indices are undefined, because when you load the page, the POST array is empty, and you cannot try to look at e.g., $_POST['description'];

do:
if(isset($_POST['description']))
{
// retrieve vars here
}

You do not use the right var here:
quantity='$co_quantity'
shoud be
quantity='$quantity'

[Roger_Ramjet]

And especially here

$ref = $_POST['item_code'];
item_code='$item_code' ";

So like I said 'use the right name'.

[cotton]

dbView_Item.php

$id = isset($POST['id']);
$item_code = isset($POST['item_code']);
$description = isset($POST['description']);
$quantity = isset($POST['quantity']);
$category = isset($POST['category']);
$c_qty = isset($POST['c_qty']);
$co_qty = isset($_POST['co_qty']);

if(isset($_POST['quantity']) > 0)
{
$co_qty = $quantity - $c_qty;
}

$query = "UPDATE stationary SET co_qty='$co_qty', description='$description', category='$category' where item_code='$id' ";
mysql_query($query) or die("not insert");

View.php

<td><form name="form1" method="post" action="dbView_Item.php">
<table width="80%" border="1" align="center" cellpadding="0" cellspacing="1" bordercolor="#CCCCCC">
<tr>
<td width="18%" bgcolor="#E0E2EB">Description : </td>
<td width="82%"><? echo $row['description']; ?></td>
<input type="hidden" name="id" value="<? echo $row['item_code']; ?>">
<tr>
<td bgcolor="#E0E2EB">Category : </td>
<td width="82%"><? echo $row['category']; ?></td>
</tr>
<tr>
<td bgcolor="#E0E2EB">Item Code : </td>
<td width="82%"><? echo $row['item_code']; ?></td>

                              <tr>
                                <td bgcolor="#E0E2EB">Current Quantity: </td>
                                <td width="82%"><? echo $row['quantity']; ?></td>
                              </tr>

                              <tr>
                                <td bgcolor="#E0E2EB">Required Quantity  : </td>
                                <td><input name="c_qty" type="text" id="ct_qty" size="10" maxlength="10"></td>
                              </tr>

</table>
<br>
<table width="80%" border="0" align="center" cellpadding="0" cellspacing="0">
<tr>
<td width="67%"><div align="right">
<input name="Cancel" type="button" id="Cancel" value="Cancel" onClick="history.go(-1)">
<input name="Submit" type="submit" onClick="MM_validateForm('description','','R','quantity','','RisNum','item_code','','R');return document.MM_returnValue" value="Submit">

when i run it, it says "not insert"..can anyone tell me how to fix it?

[bradgrafelman]

When posting PHP code, please use the board's

bbcode tags - they make the code much, much easier to read (as well as aiding the diagnosis of syntax errors). You should edit your post now and add these bbcode tags to help others in reading/analyzing your code.

Also, this code:

$id = isset($_POST['id']);
$item_code = isset($_POST['item_code']);
$description = isset($_POST['description']);
$quantity = isset($_POST['quantity']);
$category = isset($_POST['category']);
$c_qty = isset($_POST['c_qty']);
$co_qty = isset($_POST['co_qty']);

isn't right. What you need to do is test if [man]isset/man is true... if so, go ahead and make the variable assignment, like so:

$id = (isset($_POST['id']) ? $_POST['id'] : '');
$item_code = (isset($_POST['item_code']) ? $_POST['item_code'] : '');
// and so on, for all variables

Also, this if() statement:

if(isset($_POST['quantity']) > 0)

should instead be:

if($quantity > 0)

Looks like you need to visit the manual page for [man]isset/man and see what it does.

[Roger_Ramjet]

and surely it should be

item_code='$item_code'

in your query.

If it is not then you need to rethink your naming cos doing what you are doing only confuses.

[cotton]

View.php 

<td><form name="form1" method="post" action="dbView_Item.php"> 
                                <table width="80%"  border="1" align="center" cellpadding="0" cellspacing="1" bordercolor="#CCCCCC"> 
                                  <tr> 
                                    <td width="18%" bgcolor="#E0E2EB">Description : </td> 
                                    <td width="82%"><? echo $row['description']; ?></td> 
                                      <input type="hidden" name="id" value="<? echo $row['item_code']; ?>"> 
                                  <tr> 
                                    <td bgcolor="#E0E2EB">Category  : </td> 
                                    <td width="82%"><? echo $row['category']; ?></td> 
                                  </tr> 
                                  <tr> 
                                    <td bgcolor="#E0E2EB">Item Code : </td> 
                                   <td width="82%"><? echo $row['item_code']; ?></td> 


                              <tr> 
                                <td bgcolor="#E0E2EB">Current Quantity: </td> 
                                <td width="82%"><? echo $row['quantity']; ?></td> 
                              </tr> 

                              <tr> 
                                <td bgcolor="#E0E2EB">Required Quantity  : </td> 
                                <td><input name="c_qty" type="text" id="ct_qty" size="10" maxlength="10"></td> 
                              </tr> 
</table> 
                                <br> 
                                <table width="80%"  border="0" align="center" cellpadding="0" cellspacing="0"> 
                                  <tr> 
                                    <td width="67%"><div align="right"> 
                                        <input name="Cancel" type="button" id="Cancel" value="Cancel" onClick="history.go(-1)"> 
                                        <input name="Submit" type="submit" onClick="MM_validateForm('description','','R','quantity',''  ,'RisNum','item_code','','R');return document.MM_returnValue" value="Submit"> 
                                    </div></td> 
                                  </tr> 
                                </table>  

dbView_Item.php 

$id = $_POST['id']; 
$item_code = $_POST['item_code']; 
$description = $_POST['description']; 
$quantity = $_POST['quantity']; 
$category = $_POST['category']; 
$c_qty = $_POST['c_qty']; 
$co_qty = $_POST['co_qty']; 

if ( $quantity > 0 ) 
{ 
$co_qty = $quantity - $c_qty; 
} 

$query = "UPDATE stationary SET co_qty='$co_qty', description='$description', category='$category' where item_code='$id' "; 
mysql_query($query) or die("not insert");  

echo $row['description']; and the etc printing out the value that it holds at that time..e.g $row['description'];will show pencil...the $row['quantity']; shows the current quantity for the pencil in the stock..the only one that does not call any value is the required quantity :

<td bgcolor="#E0E2EB">Required Quantity : </td>
<td><input name="c_qty" type="text" id="ct_qty" size="10" maxlength="10"></td>

Because, here where i want to put the required quantity that the user want to take.
Unfortunately, after i put the required quantity, then click submit..it says not insert and the quantity in the stock doesnt changed.

[leatherback]

Well.. Your form does not submit any of the variables you are retrieving from the POST array.

As far as I can tell you only have <input name="c_qty" type="text" id="ct_qty" size="10" maxlength="10"> as form field. The otherinfo you need to submit too, or store in a session, of retrieve when processing the data.

Certainly this variable: $co_qty does not come from POST as you calculate it 2 lines down. Also this variable: $quantity should come from the database when you do your update, as otherwise people can fidget with your current stock level by manipulating your form.

I am going to be rude with you, and do apologize for it, but.. I have to ask you to sit down, and really think about what you are doing, and to rethink the whole logic. Do you UNDERSTAND any of the things you are trying to do? Please make sure you understand WHY you do WHAT you do, and if you do not understand, please start there, before trying to build shopping carts and stuff, as you are setting yourself up for a serious break of your app..

[cotton]

helo...hi..thanks for ur comments..i really appreciate it..quess im really an awful php learner am i?haha..but anyway, im not givin up..i've settled some of the problems tho and im grateful for all the helps people has givin me..just one problem left now..i managed to update the qty just tht it turn out to be zero..haha..guess my algorithm isnt right..anyone has better algorithm...help me out if u know..thnkss folks! 🆒

[Roger_Ramjet]

One thing you probably don't know is that you can do arithmetic in the query. So if you want to maintain stock levels you can write

"UPDATE stock SET quantity=(quantity - sold)"

Now I can understand you having the on-hand count in the form so that users don't try to order more than you've got (but that is what back-orders are for, so you don't loose business), but as leatherback sez, you should not use that displayed figure in your db calculation: use the existing figure in the db.

Also, you need to do it that way as 2 people can be ordering at the same time so if they both saw the displayed figure of 100 on-hand and ordered 20 then you will end up with 80 on-hand with your method instead of 60 as the second order will overlap and overwrite the first.

Now, you need to check the quantity on hand in the db as you process each order so you need to be using InnoDB tables and use Transactions to prevent overlapping orders from interfering with each other.

Transaction begin **
order 20
check 20 on-hand
process order
update on-hand
Transaction end **