I'm trying to write a controller class from a model class for a closure table.
Trying to get my head into it, but it seems difficult. I want to insert entries into a closure table.
Here's the model:
public $table;
public $closure_table = 'closures';
public function __construct($table_name = NULL, $closure_table = NULL){
parent::__construct();
$this->table = $table_name;
if ($closure_table !== NULL) {
$this->closure_table = $closure_table;
}
}
public function add($node_id, $target_id = 0) {
$sql = 'SELECT ancestor, '.$node_id.', lvl+1
FROM '.$this->closure_table.'
WHERE descendant = '.$target_id.'
UNION ALL SELECT '.$node_id.','.$node_id.',0';
$query = 'INSERT INTO '.$this->closure_table.'(ancestor, descendant, lvl) ('.$sql.')';
$result = $this->db->query($query);
return $result;
}
Error message
"Syntax error at UNION"