What are some potential pitfalls to avoid when dealing with multiple related rows in a database table in PHP?

When dealing with multiple related rows in a database table in PHP, one potential pitfall to avoid is making multiple queries to retrieve each row individually, which can lead to poor performance. Instead, it is more efficient to use a single query with a JOIN clause to retrieve all related rows in one go. Additionally, be cautious of potential data inconsistencies if updates or deletes are performed on only some of the related rows. 

// Example of using a single query with a JOIN to retrieve related rows
$query = "SELECT t1.*, t2.* FROM table1 t1 JOIN table2 t2 ON t1.id = t2.table1_id WHERE t1.id = :id";
$stmt = $pdo->prepare($query);
$stmt->execute(['id' => $id]);
$rows = $stmt->fetchAll();

Keywords

SQL injection foreign keys transactions normalization data integrity.

Related Questions