Please I need some help the Query Builder Class, this should be simple but i´ve been several days trying to solve it.
This is my Controller function, wich recieves data via POST from a IOT device:
PHP Code:
public function gettopics(){
$password = strip_tags($this->input->post('gdp'));
if ($password == GET_DATA_PASSWORD){
$device_sn = strip_tags($this->input->post('sn'));
$result = $this->Getdata_model->gettopics($device_sn);
echo "<br>#".ROOT_TOPIC."/".$result[0]['device_topic']."#".MQTT_USER."#".MQTT_PASSWORD."# "; // Line 27
}else{
echo "access denied";
}
}
And this is my model:
PHP Code:
public function gettopics($device_sn){
$this->db->SELECT('device_topic');
$this->db->FROM('devices');
$this->db->WHERE('device_sn',$device_sn);
$result = $this->db->get()->result_array();
return $result;
}
Everything works fine when the field 'device_sn' in WHERE clause is a numeric value (INT, BIGINT, etc) but i need this field to be a VARCHAR
'device_sn' is the device serial number and it contains characters too.
I get this:
A PHP Error was encountered</h4><p>Severity: Notice</p><p>Message: Undefined offset: 0</p><p>Filename: controllers/Getdata.php</p><p>Line Number: 27
Line 27 in Getdata controller is the one with "// Line 27" above. This is the same error i get when there is not device matching the serial number, but in this case in sure the serial number exists ... i only change the data type in 'device_sn' field from INT to varchar and quits working
Many thanks in advance !!!
Patrick
