Repeat query without repeating previous results

[Goldsmith]

I want to show four random ad spots at top of page (simplified code)
:

$result = mysql_query("SELECT id, company, spot FROM $mysql_tbl_spot ORDER BY RAND() LIMIT 4");
	for ($i=0;$i<mysql_num_rows($result);$i++) {
	list($spotid, $comspot, $spoturl) = mysql_fetch_row($result);
print "<td align=center valign=top><a href=\"click.php?spotid=$spotid&comid=$comspot\"><img src=\"$spoturl\" width=\"125\" height=\"50\" border=\"0\" alt=\"Click here\"></a></td>\n";

Then, after the main text, etc., I want to show another four random ad spots at the bottom of the page. Presumably I need a fresh query. How do I do that without repeating the same ad spots I've already shown at the top of the page?

I'm sure it's simple but I'm flummoxed! Any help would be really appreciated. Thanks. 🙂

[ir4z0r]

I'd add to the 2nd query a WHERE-clause:

$result = mysql-query("SELECT id, company, spot FROM $mysql_tbl_spot WHERE (id != $id1) AND (id != $id2) AND ... ORDER BY RAND() LIMIT 4");

you have to save your previous retrieved ids, of course

[Goldsmith]

Many thanks. I was thinking along the same lines.

I know this sounds dumb 😉 but what's the best way of saving the previous ids?

[ir4z0r]

in an array, I guess:

$ids = array();
$result = mysql_query("SELECT id, company, spot FROM $mysql_tbl_spot ORDER BY RAND() LIMIT 4");
for ($i=0;$i<mysql_num_rows($result);$i++)
{
  list($spotid, $comspot, $spoturl) = mysql_fetch_row($result);
  $ids[] = $spotid;
  print "<td align=center valign=top><a href=\"click.php?spotid=$spotid&comid=$comspot\"><img src=\"$spoturl\" width=\"125\" height=\"50\" border=\"0\" alt=\"Click here\"></a></td>\n";
 // ...
}

these values can obviously referenced with $ids[0] upto sizeof($ids)

[Goldsmith]

Many, many thanks!!! That works perfectly! 🙂