What potential pitfalls should be considered when using multiple WHERE clauses in a SQL query in PHP?

Using multiple WHERE clauses in a SQL query can lead to complex and potentially inefficient queries. It is important to carefully structure the query to ensure that the conditions are logically connected using AND or OR operators. Additionally, using prepared statements can help prevent SQL injection attacks. 

// Example of using prepared statements with multiple WHERE clauses in a SQL query
$pdo = new PDO('mysql:host=localhost;dbname=mydatabase', 'username', 'password');

// Define the conditions for the WHERE clauses
$condition1 = 'column1 = :value1';
$condition2 = 'column2 = :value2';

// Prepare the SQL query with the WHERE clauses
$stmt = $pdo->prepare("SELECT * FROM mytable WHERE $condition1 AND $condition2");

// Bind the values to the placeholders
$stmt->bindParam(':value1', $value1);
$stmt->bindParam(':value2', $value2);

// Execute the query
$stmt->execute();

// Fetch the results
$results = $stmt->fetchAll();

Keywords

SQL query WHERE clauses PHP MySQL error handling

Related Questions