[SOLVED] fetch_assoc/fetch_array

[thomashw]

$id = $_GET['manufacturer_id'];
$prev = mysql_query("SELECT * FROM product_prev WHERE manufacturer_id=$id");
if ($prev || mysql_num_rows($prev) > 0); {
$col = @mysql_fetch_assoc($prev); {
echo "<a href=" . $col["url"] . "><img src=" . $col["image"] . " border=\"0\"></a>";
echo "<a href=" . $col["url"] . ">{$col[name]}</a>";
echo $col['desc'];

 

In the above code, the rows have a manufacturer_id which is assigned to the $id variable. manufacturer_id can be the same among the different rows in the product_prev table (depending on the manufacturer.)

 

I'm trying to get the above code to keep looping until there are no more rows in the product_prev table with the manufacturer_id of $id.

 

Can anyone help?

 

Also, can someone explain the differences between mysql_fetch_array and mysql_fetch_assoc?

 

Thanks!

[Daniel0]

Also, can someone explain the differences between mysql_fetch_array and mysql_fetch_assoc?

 

From the manual:

mysql_fetch_array — Fetch a result row as an associative array' date=' a numeric array, or both[/quote']

mysql_fetch_assoc — Fetch a result row as an associative array

[thomashw]

Ohh, so with mysql_fetch_array you can use either the numeric ID key or the actual row name, while with mysql_fetch_assoc only the row name will work?

 

Also, if anyone can help me with my question that would be awesome.

 

Thanks!

[Daniel0]

Ohh, so with mysql_fetch_array you can use either the numeric ID key or the actual row name, while with mysql_fetch_assoc only the row name will work?

Yes. You can specify how it will work by passing either MYSQL_BOTH (default), MYSQL_ASSOC or MYSQL_NUM as the second argument.

 

$id = $_GET['manufacturer_id'];
$prev = mysql_query("SELECT * FROM product_prev WHERE manufacturer_id=$id");
if ($prev || mysql_num_rows($prev) > 0); {
$col = @mysql_fetch_assoc($prev); {
echo "<a href=" . $col["url"] . "><img src=" . $col["image"] . " border=\"0\"></a>";
echo "<a href=" . $col["url"] . ">{$col[name]}</a>";
echo $col['desc'];

 

In the above code, the rows have a manufacturer_id which is assigned to the $id variable. manufacturer_id can be the same among the different rows in the product_prev table (depending on the manufacturer.)

 

I'm trying to get the above code to keep looping until there are no more rows in the product_prev table with the manufacturer_id of $id.

 

How about this?

 

<?php
$id = intval($_GET['manufacturer_id']); // i supposed it was an integer

$prev = mysql_query("SELECT * FROM product_prev WHERE manufacturer_id={$id}");
if(mysql_num_rows($prev) > 0)
{
while($col = mysql_fetch_assoc($prev))
{
	echo "<a href=" . $col["url"] . "><img src=" . $col["image"] . " border=\"0\"></a>";
	echo "<a href=" . $col["url"] . ">{$col['name']}</a>";
	echo $col['desc'];
}
}
else {
echo "No rows with manufacturer ID {$id}";
}
?>

[thomashw]

That works perfectly, thank you!!

 

I've got another quick question - when I put while ($col = @mysql_fetch_assoc($prev)); in my above code (instead of just $col = @mysql_fetch_assoc($prev)), the code no longer called the field names (url, image, name, etc.) It just left the area blank. Can you tell me why that happened?

[Daniel0]

I've got another quick question - when I put while ($col = @mysql_fetch_assoc($prev)); in my above code (instead of just $col = @mysql_fetch_assoc($prev)), the code no longer called the field names (url, image, name, etc.) It just left the area blank. Can you tell me why that happened?

 

Well, if you do while(something); then it will run for as long as something evaluates to true, but as you have no code block it won't do anything.

[thomashw]

Sorry... what do you mean I have no code block?

[Daniel0]

Code blocks are chunks of code contained within curly braces ( { } ). Example:

if(something)
{
// here is a code block
}

while(something_else)
{
// another code block
}

The code inside the first code block is executed if something evaluates to true. The code within the second code block is executed as long as something_else evaluates to true. If the value never changes you'll have an infinite loop, i.e. the script will eventually time out and result in an error.

 

Does the exact code I provided work or do you have problems with that?

[thomashw]

Nope, the code works perfectly. Thank you for all the help!