CodeIgniter 2.0.3中活动记录中的异常回退行为

Question

以前，在CI版本2.0中，我的所有查询都运行良好，但是当我升级到2.0.3时，我的一些SELECT查询被中断了。

CI会自动添加backticks ()，但在旧版本中，它将按原样运行。

CI用户手册已指示在

db->select

作为

假

但还是没起作用。

守则如下：

class Company_model extends MY_Model
{

----------------

$this->db->select(' count('.$fieldname. ') as num_stations');
$this->db->select(" CONCAT_WS(',', clb_company.address1, clb_company.address2, clb_company.city, clb_company.state, clb_company.zipcode ) as companyAddress");
$this->db->from($this->_table);
$this->db->join($this->_table_device, $fieldname1. " = ".  $fieldname2, 'LEFT');
$this->db->where($blablafield , '0');
----------------

错误如下：

Error Number: 1064

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 
'FROM (`clb_device`) JOIN `clb_company` ON `clb_company`.`id` = `clb_device`.`com' at line 2

SELECT `clb_device`.`id` as deviceId, `clb_pricing_specifications`.`name` as pricingSpecName, `clb_company`.`name` as companyName, `clb_device`.`mac_address` as deviceMacAddress, 
`clb_device`.`reseller_model_number` as deviceModelNumber, `clb_pricing_spec_grouping`.`pricing_master_spec_id` as pricingSpecId, `clb_device`.`address` as deviceAddress, 
`clb_device`.`is_home` as deviceIsHomeCharger, CONCAT(clb_company.portal_line1, `'/'`, `clb_device`.`name)` as deviceDisplayName FROM (`clb_device`) JOIN `clb_company` 
ON `clb_company`.`id` = `clb_device`.`company_id` LEFT JOIN `clb_pricing_group_devices` ON `clb_device`.`id` = `clb_pricing_group_devices`.`device_id` and clb_pricing_group_devices.is_active = 1 
LEFT JOIN `clb_pricing_spec_grouping` ON `clb_pricing_group_devices`.`pricing_spec_id` = `clb_pricing_spec_grouping`.`pricing_master_spec_id` LEFT JOIN `clb_pricing_specifications` ON 
`clb_pricing_spec_grouping`.`pricing_spec_id` = `clb_pricing_specifications`.`id` WHERE clb_company.vendor_id is not null AND cast(substr(clb_devi
ce.software_version, 1, 3) as decimal(2,1)) > 2.0 AND clb_device.device_state > 0 GROUP BY `clb_device`.`id` ORDER BY CONCAT(trim(clb_company.portal_line1), `'/'`, trim(clb_device.name)) desc LIMIT 20

看看CONCAT(trim(clb_company.portal_line1)，'/'，trim(clb_device.name)

请提出解决办法。

Answer 1

在查询之前使用这一行：

$this->db->_protect_identifiers=false;

这将停止向生成的查询添加回退。

Answer 2

解决方案非常简单:在数据库配置文件(./application/config/database.php)中添加一个具有默认设置的数组新元素。

$db['default']['_protect_identifiers']= FALSE;

这个解决方案是为我工作，更优雅和专业。

Answer 3

所有其他答案都是老掉牙的，这一条适用于CI 2.1.4

// set this to false so that _protect_identifiers skips escaping:
$this->db->_protect_identifiers = FALSE;

// your order_by line:
$this -> db -> order_by('FIELD ( products.country_id, 2, 0, 1 )');

// important to set this back to TRUE or ALL of your queries from now on will be non-escaped:
$this->db->_protect_identifiers = TRUE;