it's a foreign key?

[eluser]gtech[/eluser]
try

Code:

$query="SELECT column_key FROM information_schema.columns
WHERE table_schema='custandusers' AND table_name='users' AND column_name='customerid'";

$foreign=$this->db->query($query);
// add this line below to your code.
print_r($foreign->result_array());

I get

Code:

Array ( [0] => Array ( [column_key] => MUL ) )

or

Code:

...
$foreign=$this->db->query($query);
$foreign=$foreign->row_array();
$type=$foreign['column_key'];
echo $type;