How to Check for Row Existence Using PDO?

Checking Row Existence Using PDO

You've encountered difficulty verifying row existence in a database using PDO. To address this issue, consider the following solution:

As suggested in the answer, you can directly check the return value of the query. Here's an example:

<code class="php">$stmt = $conn->prepare('SELECT * FROM table WHERE ID=?');
$stmt->bindParam(1, $_GET['id'], PDO::PARAM_INT);
$stmt->execute();
$row = $stmt->fetch(PDO::FETCH_ASSOC);

if (!$row) {
    echo 'Row does not exist';
}</code>

In this code, $stmt->execute() attempts to execute the query. If no row is found, $stmt->fetch() returns FALSE. This allows you to use the if (!$row) condition to determine whether the row exists.

Additionally, if you wish to check for multiple rows or avoid fetching the row, you can use the $stmt->fetchAll() method:

<code class="php">$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);

if (!$rows) {
    echo 'No rows found';
}</code>

Alternatively, you can instruct MySQL to return a 1 when a row is found:

<code class="php">$sql = 'SELECT 1 from table WHERE id = ? LIMIT 1';
$stmt = $conn->prepare($sql);
$stmt->execute([$_GET['id']]);

if ($stmt->fetchColumn()) echo 'Row found';</code>

This approach eliminates the need for fetching the row, improving efficiency.

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