[RESOLVED] var value becomes new var name

[owaring]

i have an array of categories which i query the database with via a foreach

within the for each i want to build new arrays (multidimesional) named after the parts of the category array.

i've tried $$v where $v is the value of the array this works but rewrites each time through.
$$v [] gives me Fatal error: Cannot use [] for reading in !@£/$%^/&*.php on line 13

$cats = array('system', 'archive', 'hire', 'install', 'gallery', 'contact');
foreach ($cats as $k => $v)
	{
	echo $sql = 'SELECT `title` , `name` FROM `pt_core_wwwpages` WHERE `category` = "'.$v.'"';
	$result = mysql_query($sql); 
	while ($row = mysql_fetch_array($result)) 
		{
		$$v = array($row[0],$row[1]); // this works
        $$v [] = array($row[0],$row[1]); // this is erroneous
		}
	}

any pointers where i may be going wrong?
or is there an overall better aproach to this issue?
advance thanks

[The-Master]

Well just an idea. I have used variable variables in the past and what I did, in stead of using an array was to make the variable variable include a number like this:

$i = 0;
while($i < whatever){
$v = $v . $i;
$$v = $row[$i];
}

I know that is not exactly what you want or have but I was just showing you an example. I didn't want to retype your whole code.

I hope that works.

If not you could try adding this:

$$v[$i] = array($row[0],$row[1]);

[devinemke]

you do want/need to run all those separate queries. this can all be done in a single query.

$result = mysql_query("SELECT title, name, category FROM pt_core_wwwpages WHERE category IN('system','archive','hire','install','gallery','contact')") or exit(mysql_error());
while ($row = mysql_fetch_assoc($result))
{
	$data[$row['category']][] = $row;
}

then you will have a multi-dimensional array called $data that will be grouped by category (which it what it seems you are trying to do).

[owaring]

devinemke you rock!

many thanks

[Weedpacket]

devinemke's solution is easily the better approach in this case (arrays are often a better choice than variable variables); but for future reference the syntax you were originally after was ${$v}[].

[owaring]

$result = mysql_query("SELECT title, name, category FROM pt_core_wwwpages WHERE category IN('news','hire','install','gallery','contact')") or exit(mysql_error()); 
while ($row = mysql_fetch_assoc($result)) 
{ 
    $data[$row['category']][] = $row; 
} 

the array $data is in alphabetical order, how can i get it in the order of categories in query??

[bradgrafelman]

Add an "ORDER BY" clause to your SQL query.

[owaring]

so my sql is now:

$result = mysql_query("SELECT title, name, category, tstamp FROM pt_core_wwwpages
WHERE category IN('news', 'hire', 'install', 'gallery', 'contact')
ORDER BY FIELD(category, 'news', 'hire', 'install', 'gallery', 'contact')") or exit(mysql_error()); 
while ($row = mysql_fetch_assoc($result)) 
{ 
    $data[$row['category']][] = $row; 
} 

is it possible to sort each of the 'category`arrays by 'tstamp'??

[bradgrafelman]

Of course - just add the extra column to your ORDER clause. As you'll see in the MySQL manual for Sorting Rows, the "ORDER BY" clause accepts a comma-delimited list of columns to sort by.

[owaring]

thanks for the link