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POPHP PDO with foreach and fetch
 

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    <p>The following codes:</p> <pre><code>&lt;?php try { $dbh = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $password); echo "Connection is successful!&lt;br/&gt;"; $sql = "SELECT * FROM users"; $users = $dbh-&gt;query($sql); foreach ($users as $row) { print $row["name"] . "-" . $row["sex"] ."&lt;br/&gt;"; } foreach ($users as $row) { print $row["name"] . "-" . $row["sex"] ."&lt;br/&gt;"; } $dbh = null; } catch (PDOexception $e) { echo "Error is: " . $e-&gt; etmessage(); } </code></pre> <p>OUTPUT:</p> <pre><code>Connection is successful! person A-male person B-female </code></pre> <p>Running "foreach" twice is not my purpose, I'm just curious why TWO "foreach" statements only output the result once?</p> <p>Following is the similar case:</p> <pre><code>&lt;?php try { $dbh = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $password); echo "Connection is successful!&lt;br/&gt;"; $sql = "SELECT * FROM users"; $users = $dbh-&gt;query($sql); foreach ($users as $row) { print $row["name"] . "-" . $row["sex"] ."&lt;br/&gt;"; } echo "&lt;br/&gt;"; $result = $users-&gt;fetch(PDO::FETCH_ASSOC); foreach($result as $key =&gt; $value) { echo $key . "-" . $value . "&lt;br/&gt;"; } $dbh = null; } catch (PDOexception $e) { echo "Error is: " . $e-&gt; etmessage(); } </code></pre> <p>OUTPUT:</p> <pre><code>Connection is successful! person A-male person B-female SCREAM: Error suppression ignored for Warning: Invalid argument supplied for foreach() </code></pre> <p>But when I delete the first "foreach" from the above codes, the output will become normal:</p> <pre><code>&lt;?php try { $dbh = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $password); echo "Connection is successful!&lt;br/&gt;"; $sql = "SELECT * FROM users"; $users = $dbh-&gt;query($sql); echo "&lt;br/&gt;"; $result = $users-&gt;fetch(PDO::FETCH_ASSOC); foreach($result as $key =&gt; $value) { echo $key . "-" . $value . "&lt;br/&gt;"; } $dbh = null; } catch (PDOexception $e) { echo "Error is: " . $e-&gt; etmessage(); } </code></pre> <p>OUTPUT:</p> <pre><code>Connection is successful! user_id-0000000001 name-person A sex-male </code></pre> <p>Anyone know why does this happen? I'm just a PHP beginner, thanks for your help!</p>
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