How can you select from a database all records where the value in a certain field is less than a given threshold?

To select all records from a database where the value in a specific field is less than a given threshold, an SQL query with a WHERE condition and the comparison operator < is used.

Example in PHP using PDO:

$threshold = 100;
$sql = "SELECT * FROM table_name WHERE field_name < :threshold";
$stmt = $pdo->prepare($sql);
$stmt->execute(['threshold' => $threshold]);
$results = $stmt->fetchAll(PDO::FETCH_ASSOC);

Here, field_name < :threshold selects all records where the field value is less than the threshold.