将 SQL 查询结果插入到单独的 PHP 变量中

Question

I'm trying to make an ad system with PHP pdo. How can I get result id's of the following SQL query into my PHP variables?

SELECT id FROM ads, ( SELECT id AS sid FROM ads WHERE position="A" ORDER BY RAND( ) LIMIT 5 ) tmp WHERE ads.id = tmp.sid

I just don't know how to get those values in the variables like this:

$ad_1 = result[1]
$ad_2 = result[2]
$ad_3 = result[3]
$ad_4 = result[4]
$ad_5 = result[5]

With the help of those variables ($ad_1...5) I could display unique and random ads in different places, get correct data, and update ad clicks/views...

Answer 1

try this :

$begin = "ad_";
for($i = 0; $i < 6 ; $i++) {
    $($begin.$i) = $result[$i];
}

(assuming you array $result is previously defined)

Answer 2

Best to get into the habit of using prepared statements like this:

<?php
$adIds = array();
$position = 'A'; // probably set dynamicaly
$stmt = $dbh->prepare("SELECT id FROM ads, ( SELECT id AS sid FROM ads WHERE position=? ORDER BY RAND( ) LIMIT 5 ) tmp WHERE ads.id = tmp.sid");
$stmt->bindParam(1, $position);
if ($stmt->execute()) {
  while ($row = $stmt->fetch()) {
    $adIds[] = $row[0];
  }
}
?>

$adIds is now an array containing all the ids returned from the select statement.