/**
* @internal
*/
protected function loadKeys()
{
if (!isset($this->keys)) {
$this->keys = array();
$sql = "SELECT TABLE_NAME AS `table_name`, COLUMN_NAME AS `column_name`, " . "REFERENCED_COLUMN_NAME AS `referenced_column_name`, REFERENCED_TABLE_NAME AS `referenced_table_name` " . "FROM information_schema.KEY_COLUMN_USAGE " . "WHERE TABLE_SCHEMA = DATABASE() " . "AND REFERENCED_TABLE_SCHEMA = DATABASE()";
$result = $this->connection->query($sql);
$result->setFetchMode(PDO::FETCH_ASSOC);
foreach ($result as $row) {
$this->keys[] = $row;
}
}
return $this->keys;
}
