PHP PDO rowCount

The PDO class in PHP provides an interface to connect and interact with databases in a consistent manner. The rowCount method is a part of PDOStatement class, which is used to retrieve the number of rows affected or returned by a database operation.

Syntax

int PDOStatement::rowCount()

Description

The rowCount method returns the number of rows affected by the last executed SQL statement. It can be used for various types of database operations like INSERT, UPDATE, DELETE, or SELECT statements.

When executing a SELECT statement, rowCount returns the number of rows returned by the SELECT statement. For other statements like INSERT, UPDATE, or DELETE, it returns the number of rows affected by the statement.

Example

Here is an example that demonstrates the usage of rowCount method:

<?php
$pdo = new PDO("mysql:host=localhost;dbname=test", "username", "password");

$sql = "UPDATE users SET status = 1 WHERE id = ?";
$statement = $pdo->prepare($sql);
$statement->bindParam(1, $id);
$statement->execute();

$rowCount = $statement->rowCount();

echo "Number of rows affected: " . $rowCount;
?>

In the above example, we connect to a MySQL database using PDO and prepare an UPDATE statement to update the status of a user based on their ID. After executing the statement, we use rowCount to get the number of affected rows.

Notes

• rowCount may not return the correct number of rows for SELECT statements on certain databases, as it depends on driver implementation.
• For some databases, rowCount may return 0 for SELECT statements, in which case it's recommended to use fetch or fetchAll to determine the number of returned rows.

For more information, refer to the PHP manual on PDOStatement::rowCount.