How can improper syntax in SQL queries impact the functionality of PHP scripts?

Improper syntax in SQL queries can lead to errors in PHP scripts as the queries may not execute correctly, resulting in unexpected behavior or no data being retrieved. To solve this issue, it is essential to ensure that SQL queries are properly formatted and free of syntax errors before executing them in PHP scripts.

// Correct SQL query syntax example
$sql = "SELECT * FROM users WHERE id = 1";
$result = mysqli_query($conn, $sql);
if ($result) {
    // Process the query result
} else {
    echo "Error executing query: " . mysqli_error($conn);
}