Question

EDIT: For anyone finding this at a later date CI will use alot of memory in these sorts of circumstances since it will create an object for every row (using result_array() doesn’t seem much better), so the best bet is just to use PHP’s built in mysql functions. If you’re using MYSQLI you can access the connection link like so:

$this->db->conn_id

I’m trying to run a script through the command line (testing for what will be a cronjob), what the script does is irrelevant since it is failing at the first select and doesn’t get any further.

I am using Codeigniter 2.0.3.

My table looks like this:

CREATE TABLE IF NOT EXISTS `graphic_files` (
  `graphic_file_id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `graphic_file_style_id` tinyint(2) unsigned NOT NULL,
  `graphic_file_fm_id` bigint(20) unsigned DEFAULT NULL,
  `graphic_file_config_line` varchar(255) NOT NULL,
  `graphic_file_config_line_hash` varchar(32) NOT NULL,
  `graphic_file_location` varchar(255) DEFAULT NULL,
  `graphic_file_pack_id` int(10) unsigned NOT NULL,
  `graphic_file_enabled` tinyint(1) NOT NULL,
  `graphic_file_alternative` tinyint(1) NOT NULL,
  `graphic_file_version` decimal(4,2) NOT NULL,
  `graphic_file_time_added` int(11) unsigned NOT NULL,
  `graphic_file_time_modified` int(11) unsigned NOT NULL,
  `graphic_file_size` int(11) unsigned NOT NULL,
  PRIMARY KEY (`graphic_file_id`),
  KEY `graphic_file_style_id` (`graphic_file_style_id`),
  KEY `graphic_file_fm_id` (`graphic_file_fm_id`),
  KEY `graphic_file_config_line_hash` (`graphic_file_config_line_hash`),
  KEY `graphic_file_pack_id` (`graphic_file_pack_id`),
  KEY `graphic_file_enabled` (`graphic_file_enabled`),
  KEY `graphic_file_version` (`graphic_file_version`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=240752 ;

There are 240,000 rows.

I am trying to select around 120,000 of them with this query:

SELECT * FROM graphic_files WHERE graphic_file_enabled = 0 AND graphic_file_style_id = 5

But I get an allowed memory size error like so:

Allowed memory size of 268435456 bytes exhausted (tried to allocate 92
bytes) in
xxx/codeigniter_2.0.3/database/drivers/mysqli/mysqli_result.php on
line 167

I realise the simple answer is that i’m out of memory, but this seems ridiculous for simply doing a select query, especially with a high allowed memory size of 256mb.

Can anybody suggest a reason for this? Could it be to do with codeigniter and the way it builds the results object?

Answer 1

With big data u need to use mysql resource instead of CI functions

$result = $this->db->query($sql);
$resource = $result->result_id;
while($row = @mysql_fetch_assoc($resource)) {
    // do the magic
}