/**
* Set a column to order by and the direction to do so.
* Update 2013-12-06 : originally Field only, didn't make sense not to
* use a string as well because the order is supposed to specific to this
* table.
* @param mixed $column
* @param string $direction Either ASC or DESC
*/
public function addOrderBy($column, $direction = 'ASC')
{
if (!$column instanceof \Database\Field && is_string($column)) {
$column = $this->getField($column);
}
static $allowed_directions = array('ASC', 'DESC', 'RAND', 'RANDOM');
$direction = trim(strtoupper($direction));
if (!in_array($direction, $allowed_directions)) {
throw new \Exception(t('Unknown order direction: %s', $direction));
}
// If a random call, return the db os specific function call.
if ($direction == 'RAND' || $direction == 'RANDOM') {
$direction = $this->db->getRandomCall();
}
if (DATABASE_CHECK_COLUMNS && !$this->columnExists($column)) {
throw new \Exception(t('Table column "%s" is not known', $column));
} else {
if ($column->hasAlias()) {
$this->orders[] = $column->getAlias() . " {$direction}";
} else {
$this->orders[] = $column->getFullName() . " {$direction}";
}
}
return $this;
}
