/**
* Fetch all results for the supplied SQL query using a PHP generator.
*
* This approach uses less memory, but the result set has a forward-only cursor.
*
* The SQL query can be a simple string or a Select object. The bind array
* should supply values for all the parameters, either named or numeric, in
* the query. And the fetch mode should match one of these 4 class constants
* from \Dewdrop\Db\Adapter: ARRAY_A, ARRAY_N, OBJECT, or OBJECT_K.
*
* @param string|Select $sql
* @param array $bind
* @param string $fetchMode
* @return \Generator
* @throws Exception
*/
public function fetchAllWithGenerator($sql, $bind = [], $fetchMode = null)
{
if (null === $fetchMode) {
$fetchMode = Adapter::ARRAY_A;
}
$sql = $this->adapter->prepare($sql, $bind);
/* @var PDO $pdo */
$pdo = $this->getConnection();
$pdoFetchClass = null;
switch ($fetchMode) {
case Adapter::ARRAY_A:
$pdoFetchMode = PDO::FETCH_ASSOC;
break;
case Adapter::ARRAY_N:
$pdoFetchMode = PDO::FETCH_NUM;
break;
case Adapter::OBJECT:
// intentional fall-through
// intentional fall-through
case Adapter::OBJECT_K:
$pdoFetchMode = PDO::FETCH_OBJ;
break;
default:
throw new Exception("Unsupported fetch mode '{$fetchMode}'");
}
$statement = $pdo->query($sql, $pdoFetchMode);
while (false !== ($row = $statement->fetch())) {
(yield $row);
}
}
/**
* Run the supplied query, binding the supplied data to the statement
* prior to execution.
*
* @param string|\Dewdrop\Db\Select $sql
* @param array $bind
* @return mixed
*/
public function query($sql, $bind = array())
{
return $this->execWpdb($this->wpdb->query($this->adapter->prepare($sql, $bind)));
}